Fix misleading verification output when -v is used with -bv and aliasing
[exim.git] / src / src / verify.c
CommitLineData
e6f6568e 1/* $Cambridge: exim/src/src/verify.c,v 1.40 2006/10/03 10:25:55 ph10 Exp $ */
059ec3d9
PH
2
3/*************************************************
4* Exim - an Internet mail transport agent *
5*************************************************/
6
d7d7b7b9 7/* Copyright (c) University of Cambridge 1995 - 2006 */
059ec3d9
PH
8/* See the file NOTICE for conditions of use and distribution. */
9
10/* Functions concerned with verifying things. The original code for callout
11caching was contributed by Kevin Fleming (but I hacked it around a bit). */
12
13
14#include "exim.h"
15
16
17/* Structure for caching DNSBL lookups */
18
19typedef struct dnsbl_cache_block {
20 dns_address *rhs;
21 uschar *text;
22 int rc;
23 BOOL text_set;
24} dnsbl_cache_block;
25
26
27/* Anchor for DNSBL cache */
28
29static tree_node *dnsbl_cache = NULL;
30
31
32
33/*************************************************
34* Retrieve a callout cache record *
35*************************************************/
36
37/* If a record exists, check whether it has expired.
38
39Arguments:
40 dbm_file an open hints file
41 key the record key
42 type "address" or "domain"
43 positive_expire expire time for positive records
44 negative_expire expire time for negative records
45
46Returns: the cache record if a non-expired one exists, else NULL
47*/
48
49static dbdata_callout_cache *
50get_callout_cache_record(open_db *dbm_file, uschar *key, uschar *type,
51 int positive_expire, int negative_expire)
52{
53BOOL negative;
54int length, expire;
55time_t now;
56dbdata_callout_cache *cache_record;
57
58cache_record = dbfn_read_with_length(dbm_file, key, &length);
59
60if (cache_record == NULL)
61 {
62 HDEBUG(D_verify) debug_printf("callout cache: no %s record found\n", type);
63 return NULL;
64 }
65
66/* We treat a record as "negative" if its result field is not positive, or if
67it is a domain record and the postmaster field is negative. */
68
69negative = cache_record->result != ccache_accept ||
70 (type[0] == 'd' && cache_record->postmaster_result == ccache_reject);
71expire = negative? negative_expire : positive_expire;
72now = time(NULL);
73
74if (now - cache_record->time_stamp > expire)
75 {
76 HDEBUG(D_verify) debug_printf("callout cache: %s record expired\n", type);
77 return NULL;
78 }
79
80/* If this is a non-reject domain record, check for the obsolete format version
81that doesn't have the postmaster and random timestamps, by looking at the
82length. If so, copy it to a new-style block, replicating the record's
83timestamp. Then check the additional timestamps. (There's no point wasting
84effort if connections are rejected.) */
85
86if (type[0] == 'd' && cache_record->result != ccache_reject)
87 {
88 if (length == sizeof(dbdata_callout_cache_obs))
89 {
90 dbdata_callout_cache *new = store_get(sizeof(dbdata_callout_cache));
91 memcpy(new, cache_record, length);
92 new->postmaster_stamp = new->random_stamp = new->time_stamp;
93 cache_record = new;
94 }
95
96 if (now - cache_record->postmaster_stamp > expire)
97 cache_record->postmaster_result = ccache_unknown;
98
99 if (now - cache_record->random_stamp > expire)
100 cache_record->random_result = ccache_unknown;
101 }
102
103HDEBUG(D_verify) debug_printf("callout cache: found %s record\n", type);
104return cache_record;
105}
106
107
108
109/*************************************************
110* Do callout verification for an address *
111*************************************************/
112
113/* This function is called from verify_address() when the address has routed to
114a host list, and a callout has been requested. Callouts are expensive; that is
115why a cache is used to improve the efficiency.
116
117Arguments:
118 addr the address that's been routed
119 host_list the list of hosts to try
120 tf the transport feedback block
121
122 ifstring "interface" option from transport, or NULL
123 portstring "port" option from transport, or NULL
124 protocolstring "protocol" option from transport, or NULL
125 callout the per-command callout timeout
4deaf07d
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126 callout_overall the overall callout timeout (if < 0 use 4*callout)
127 callout_connect the callout connection timeout (if < 0 use callout)
059ec3d9
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128 options the verification options - these bits are used:
129 vopt_is_recipient => this is a recipient address
130 vopt_callout_no_cache => don't use callout cache
2a4be8f9 131 vopt_callout_fullpm => if postmaster check, do full one
059ec3d9
PH
132 vopt_callout_random => do the "random" thing
133 vopt_callout_recipsender => use real sender for recipient
134 vopt_callout_recippmaster => use postmaster for recipient
135 se_mailfrom MAIL FROM address for sender verify; NULL => ""
136 pm_mailfrom if non-NULL, do the postmaster check with this sender
137
138Returns: OK/FAIL/DEFER
139*/
140
141static int
142do_callout(address_item *addr, host_item *host_list, transport_feedback *tf,
8e669ac1 143 int callout, int callout_overall, int callout_connect, int options,
4deaf07d 144 uschar *se_mailfrom, uschar *pm_mailfrom)
059ec3d9
PH
145{
146BOOL is_recipient = (options & vopt_is_recipient) != 0;
147BOOL callout_no_cache = (options & vopt_callout_no_cache) != 0;
148BOOL callout_random = (options & vopt_callout_random) != 0;
149
150int yield = OK;
2b1c6e3a 151int old_domain_cache_result = ccache_accept;
059ec3d9
PH
152BOOL done = FALSE;
153uschar *address_key;
154uschar *from_address;
155uschar *random_local_part = NULL;
750af86e 156uschar *save_deliver_domain = deliver_domain;
8e669ac1 157uschar **failure_ptr = is_recipient?
2c7db3f5 158 &recipient_verify_failure : &sender_verify_failure;
059ec3d9
PH
159open_db dbblock;
160open_db *dbm_file = NULL;
161dbdata_callout_cache new_domain_record;
162dbdata_callout_cache_address new_address_record;
163host_item *host;
164time_t callout_start_time;
165
166new_domain_record.result = ccache_unknown;
167new_domain_record.postmaster_result = ccache_unknown;
168new_domain_record.random_result = ccache_unknown;
169
170memset(&new_address_record, 0, sizeof(new_address_record));
171
172/* For a recipient callout, the key used for the address cache record must
173include the sender address if we are using the real sender in the callout,
174because that may influence the result of the callout. */
175
176address_key = addr->address;
177from_address = US"";
178
179if (is_recipient)
180 {
181 if ((options & vopt_callout_recipsender) != 0)
182 {
183 address_key = string_sprintf("%s/<%s>", addr->address, sender_address);
184 from_address = sender_address;
185 }
186 else if ((options & vopt_callout_recippmaster) != 0)
187 {
188 address_key = string_sprintf("%s/<postmaster@%s>", addr->address,
189 qualify_domain_sender);
190 from_address = string_sprintf("postmaster@%s", qualify_domain_sender);
191 }
192 }
193
194/* For a sender callout, we must adjust the key if the mailfrom address is not
195empty. */
196
197else
198 {
199 from_address = (se_mailfrom == NULL)? US"" : se_mailfrom;
200 if (from_address[0] != 0)
201 address_key = string_sprintf("%s/<%s>", addr->address, from_address);
202 }
203
204/* Open the callout cache database, it it exists, for reading only at this
205stage, unless caching has been disabled. */
206
207if (callout_no_cache)
208 {
209 HDEBUG(D_verify) debug_printf("callout cache: disabled by no_cache\n");
210 }
211else if ((dbm_file = dbfn_open(US"callout", O_RDWR, &dbblock, FALSE)) == NULL)
212 {
213 HDEBUG(D_verify) debug_printf("callout cache: not available\n");
214 }
215
216/* If a cache database is available see if we can avoid the need to do an
217actual callout by making use of previously-obtained data. */
218
219if (dbm_file != NULL)
220 {
221 dbdata_callout_cache_address *cache_address_record;
222 dbdata_callout_cache *cache_record = get_callout_cache_record(dbm_file,
223 addr->domain, US"domain",
224 callout_cache_domain_positive_expire,
225 callout_cache_domain_negative_expire);
226
227 /* If an unexpired cache record was found for this domain, see if the callout
228 process can be short-circuited. */
229
230 if (cache_record != NULL)
231 {
2b1c6e3a
PH
232 /* In most cases, if an early command (up to and including MAIL FROM:<>)
233 was rejected, there is no point carrying on. The callout fails. However, if
234 we are doing a recipient verification with use_sender or use_postmaster
235 set, a previous failure of MAIL FROM:<> doesn't count, because this time we
236 will be using a non-empty sender. We have to remember this situation so as
237 not to disturb the cached domain value if this whole verification succeeds
238 (we don't want it turning into "accept"). */
239
240 old_domain_cache_result = cache_record->result;
241
242 if (cache_record->result == ccache_reject ||
243 (*from_address == 0 && cache_record->result == ccache_reject_mfnull))
059ec3d9
PH
244 {
245 setflag(addr, af_verify_nsfail);
246 HDEBUG(D_verify)
247 debug_printf("callout cache: domain gave initial rejection, or "
248 "does not accept HELO or MAIL FROM:<>\n");
249 setflag(addr, af_verify_nsfail);
250 addr->user_message = US"(result of an earlier callout reused).";
251 yield = FAIL;
8e669ac1 252 *failure_ptr = US"mail";
059ec3d9
PH
253 goto END_CALLOUT;
254 }
255
256 /* If a previous check on a "random" local part was accepted, we assume
257 that the server does not do any checking on local parts. There is therefore
258 no point in doing the callout, because it will always be successful. If a
259 random check previously failed, arrange not to do it again, but preserve
260 the data in the new record. If a random check is required but hasn't been
261 done, skip the remaining cache processing. */
262
263 if (callout_random) switch(cache_record->random_result)
264 {
265 case ccache_accept:
266 HDEBUG(D_verify)
267 debug_printf("callout cache: domain accepts random addresses\n");
268 goto END_CALLOUT; /* Default yield is OK */
269
270 case ccache_reject:
271 HDEBUG(D_verify)
272 debug_printf("callout cache: domain rejects random addresses\n");
273 callout_random = FALSE;
274 new_domain_record.random_result = ccache_reject;
275 new_domain_record.random_stamp = cache_record->random_stamp;
276 break;
277
278 default:
279 HDEBUG(D_verify)
280 debug_printf("callout cache: need to check random address handling "
281 "(not cached or cache expired)\n");
282 goto END_CACHE;
283 }
284
285 /* If a postmaster check is requested, but there was a previous failure,
286 there is again no point in carrying on. If a postmaster check is required,
287 but has not been done before, we are going to have to do a callout, so skip
288 remaining cache processing. */
289
290 if (pm_mailfrom != NULL)
291 {
292 if (cache_record->postmaster_result == ccache_reject)
293 {
294 setflag(addr, af_verify_pmfail);
295 HDEBUG(D_verify)
296 debug_printf("callout cache: domain does not accept "
297 "RCPT TO:<postmaster@domain>\n");
298 yield = FAIL;
8e669ac1 299 *failure_ptr = US"postmaster";
059ec3d9
PH
300 setflag(addr, af_verify_pmfail);
301 addr->user_message = US"(result of earlier verification reused).";
302 goto END_CALLOUT;
303 }
304 if (cache_record->postmaster_result == ccache_unknown)
305 {
306 HDEBUG(D_verify)
307 debug_printf("callout cache: need to check RCPT "
308 "TO:<postmaster@domain> (not cached or cache expired)\n");
309 goto END_CACHE;
310 }
311
312 /* If cache says OK, set pm_mailfrom NULL to prevent a redundant
313 postmaster check if the address itself has to be checked. Also ensure
314 that the value in the cache record is preserved (with its old timestamp).
315 */
316
317 HDEBUG(D_verify) debug_printf("callout cache: domain accepts RCPT "
318 "TO:<postmaster@domain>\n");
319 pm_mailfrom = NULL;
320 new_domain_record.postmaster_result = ccache_accept;
321 new_domain_record.postmaster_stamp = cache_record->postmaster_stamp;
322 }
323 }
324
325 /* We can't give a result based on information about the domain. See if there
326 is an unexpired cache record for this specific address (combined with the
327 sender address if we are doing a recipient callout with a non-empty sender).
328 */
329
330 cache_address_record = (dbdata_callout_cache_address *)
331 get_callout_cache_record(dbm_file,
332 address_key, US"address",
333 callout_cache_positive_expire,
334 callout_cache_negative_expire);
335
336 if (cache_address_record != NULL)
337 {
338 if (cache_address_record->result == ccache_accept)
339 {
340 HDEBUG(D_verify)
341 debug_printf("callout cache: address record is positive\n");
342 }
343 else
344 {
345 HDEBUG(D_verify)
346 debug_printf("callout cache: address record is negative\n");
347 addr->user_message = US"Previous (cached) callout verification failure";
8e669ac1 348 *failure_ptr = US"recipient";
059ec3d9
PH
349 yield = FAIL;
350 }
351 goto END_CALLOUT;
352 }
353
354 /* Close the cache database while we actually do the callout for real. */
355
356 END_CACHE:
357 dbfn_close(dbm_file);
358 dbm_file = NULL;
359 }
360
361/* The information wasn't available in the cache, so we have to do a real
362callout and save the result in the cache for next time, unless no_cache is set,
363or unless we have a previously cached negative random result. If we are to test
364with a random local part, ensure that such a local part is available. If not,
365log the fact, but carry on without randomming. */
366
367if (callout_random && callout_random_local_part != NULL)
368 {
369 random_local_part = expand_string(callout_random_local_part);
370 if (random_local_part == NULL)
371 log_write(0, LOG_MAIN|LOG_PANIC, "failed to expand "
372 "callout_random_local_part: %s", expand_string_message);
373 }
374
4deaf07d
PH
375/* Default the connect and overall callout timeouts if not set, and record the
376time we are starting so that we can enforce it. */
059ec3d9
PH
377
378if (callout_overall < 0) callout_overall = 4 * callout;
4deaf07d 379if (callout_connect < 0) callout_connect = callout;
059ec3d9
PH
380callout_start_time = time(NULL);
381
382/* Now make connections to the hosts and do real callouts. The list of hosts
383is passed in as an argument. */
384
385for (host = host_list; host != NULL && !done; host = host->next)
386 {
387 smtp_inblock inblock;
388 smtp_outblock outblock;
389 int host_af;
390 int port = 25;
8e669ac1 391 BOOL send_quit = TRUE;
26da7e20 392 uschar *active_hostname = smtp_active_hostname;
059ec3d9
PH
393 uschar *helo = US"HELO";
394 uschar *interface = NULL; /* Outgoing interface to use; NULL => any */
395 uschar inbuffer[4096];
396 uschar outbuffer[1024];
397 uschar responsebuffer[4096];
398
399 clearflag(addr, af_verify_pmfail); /* postmaster callout flag */
400 clearflag(addr, af_verify_nsfail); /* null sender callout flag */
401
402 /* Skip this host if we don't have an IP address for it. */
403
404 if (host->address == NULL)
405 {
406 DEBUG(D_verify) debug_printf("no IP address for host name %s: skipping\n",
407 host->name);
408 continue;
409 }
410
411 /* Check the overall callout timeout */
412
413 if (time(NULL) - callout_start_time >= callout_overall)
414 {
415 HDEBUG(D_verify) debug_printf("overall timeout for callout exceeded\n");
416 break;
417 }
418
419 /* Set IPv4 or IPv6 */
420
421 host_af = (Ustrchr(host->address, ':') == NULL)? AF_INET:AF_INET6;
422
de3a88fb
PH
423 /* Expand and interpret the interface and port strings. The latter will not
424 be used if there is a host-specific port (e.g. from a manualroute router).
425 This has to be delayed till now, because they may expand differently for
426 different hosts. If there's a failure, log it, but carry on with the
427 defaults. */
059ec3d9
PH
428
429 deliver_host = host->name;
430 deliver_host_address = host->address;
750af86e 431 deliver_domain = addr->domain;
de3a88fb 432
059ec3d9
PH
433 if (!smtp_get_interface(tf->interface, host_af, addr, NULL, &interface,
434 US"callout") ||
435 !smtp_get_port(tf->port, addr, &port, US"callout"))
436 log_write(0, LOG_MAIN|LOG_PANIC, "<%s>: %s", addr->address,
437 addr->message);
de3a88fb 438
26da7e20
PH
439 /* Expand the helo_data string to find the host name to use. */
440
441 if (tf->helo_data != NULL)
442 {
443 uschar *s = expand_string(tf->helo_data);
444 if (active_hostname == NULL)
445 log_write(0, LOG_MAIN|LOG_PANIC, "<%s>: failed to expand transport's "
446 "helo_data value for callout: %s", expand_string_message);
447 else active_hostname = s;
448 }
449
059ec3d9 450 deliver_host = deliver_host_address = NULL;
750af86e 451 deliver_domain = save_deliver_domain;
059ec3d9
PH
452
453 /* Set HELO string according to the protocol */
454
455 if (Ustrcmp(tf->protocol, "lmtp") == 0) helo = US"LHLO";
456
457 HDEBUG(D_verify) debug_printf("interface=%s port=%d\n", interface, port);
458
459 /* Set up the buffer for reading SMTP response packets. */
460
461 inblock.buffer = inbuffer;
462 inblock.buffersize = sizeof(inbuffer);
463 inblock.ptr = inbuffer;
464 inblock.ptrend = inbuffer;
465
466 /* Set up the buffer for holding SMTP commands while pipelining */
467
468 outblock.buffer = outbuffer;
469 outblock.buffersize = sizeof(outbuffer);
470 outblock.ptr = outbuffer;
471 outblock.cmd_count = 0;
472 outblock.authenticating = FALSE;
473
474 /* Connect to the host; on failure, just loop for the next one, but we
4deaf07d 475 set the error for the last one. Use the callout_connect timeout. */
059ec3d9
PH
476
477 inblock.sock = outblock.sock =
4deaf07d 478 smtp_connect(host, host_af, port, interface, callout_connect, TRUE);
059ec3d9
PH
479 if (inblock.sock < 0)
480 {
481 addr->message = string_sprintf("could not connect to %s [%s]: %s",
482 host->name, host->address, strerror(errno));
483 continue;
484 }
485
2b1c6e3a
PH
486 /* Wait for initial response, and send HELO. The smtp_write_command()
487 function leaves its command in big_buffer. This is used in error responses.
488 Initialize it in case the connection is rejected. */
059ec3d9
PH
489
490 Ustrcpy(big_buffer, "initial connection");
491
492 done =
493 smtp_read_response(&inblock, responsebuffer, sizeof(responsebuffer),
494 '2', callout) &&
059ec3d9 495 smtp_write_command(&outblock, FALSE, "%s %s\r\n", helo,
26da7e20 496 active_hostname) >= 0 &&
059ec3d9 497 smtp_read_response(&inblock, responsebuffer, sizeof(responsebuffer),
2b1c6e3a 498 '2', callout);
059ec3d9 499
2b1c6e3a
PH
500 /* Failure to accept HELO is cached; this blocks the whole domain for all
501 senders. I/O errors and defer responses are not cached. */
502
503 if (!done)
504 {
505 *failure_ptr = US"mail"; /* At or before MAIL */
506 if (errno == 0 && responsebuffer[0] == '5')
507 {
508 setflag(addr, af_verify_nsfail);
509 new_domain_record.result = ccache_reject;
510 }
511 }
512
513 /* Send the MAIL command */
514
515 else done =
059ec3d9
PH
516 smtp_write_command(&outblock, FALSE, "MAIL FROM:<%s>\r\n",
517 from_address) >= 0 &&
518 smtp_read_response(&inblock, responsebuffer, sizeof(responsebuffer),
519 '2', callout);
520
2b1c6e3a
PH
521 /* If the host does not accept MAIL FROM:<>, arrange to cache this
522 information, but again, don't record anything for an I/O error or a defer. Do
523 not cache rejections of MAIL when a non-empty sender has been used, because
524 that blocks the whole domain for all senders. */
059ec3d9
PH
525
526 if (!done)
527 {
2b1c6e3a 528 *failure_ptr = US"mail"; /* At or before MAIL */
059ec3d9
PH
529 if (errno == 0 && responsebuffer[0] == '5')
530 {
531 setflag(addr, af_verify_nsfail);
2b1c6e3a
PH
532 if (from_address[0] == 0)
533 new_domain_record.result = ccache_reject_mfnull;
059ec3d9
PH
534 }
535 }
536
537 /* Otherwise, proceed to check a "random" address (if required), then the
538 given address, and the postmaster address (if required). Between each check,
539 issue RSET, because some servers accept only one recipient after MAIL
2b1c6e3a
PH
540 FROM:<>.
541
542 Before doing this, set the result in the domain cache record to "accept",
543 unless its previous value was ccache_reject_mfnull. In that case, the domain
544 rejects MAIL FROM:<> and we want to continue to remember that. When that is
545 the case, we have got here only in the case of a recipient verification with
546 a non-null sender. */
059ec3d9
PH
547
548 else
549 {
2b1c6e3a
PH
550 new_domain_record.result =
551 (old_domain_cache_result == ccache_reject_mfnull)?
552 ccache_reject_mfnull: ccache_accept;
059ec3d9
PH
553
554 /* Do the random local part check first */
555
556 if (random_local_part != NULL)
557 {
558 uschar randombuffer[1024];
559 BOOL random_ok =
560 smtp_write_command(&outblock, FALSE,
561 "RCPT TO:<%.1000s@%.1000s>\r\n", random_local_part,
562 addr->domain) >= 0 &&
563 smtp_read_response(&inblock, randombuffer,
564 sizeof(randombuffer), '2', callout);
565
566 /* Remember when we last did a random test */
567
568 new_domain_record.random_stamp = time(NULL);
569
570 /* If accepted, we aren't going to do any further tests below. */
571
572 if (random_ok)
573 {
574 new_domain_record.random_result = ccache_accept;
575 }
576
577 /* Otherwise, cache a real negative response, and get back to the right
578 state to send RCPT. Unless there's some problem such as a dropped
579 connection, we expect to succeed, because the commands succeeded above. */
580
581 else if (errno == 0)
582 {
583 if (randombuffer[0] == '5')
584 new_domain_record.random_result = ccache_reject;
585
586 done =
587 smtp_write_command(&outblock, FALSE, "RSET\r\n") >= 0 &&
588 smtp_read_response(&inblock, responsebuffer, sizeof(responsebuffer),
589 '2', callout) &&
590
90e9ce59
PH
591 smtp_write_command(&outblock, FALSE, "MAIL FROM:<%s>\r\n",
592 from_address) >= 0 &&
059ec3d9
PH
593 smtp_read_response(&inblock, responsebuffer, sizeof(responsebuffer),
594 '2', callout);
595 }
596 else done = FALSE; /* Some timeout/connection problem */
597 } /* Random check */
598
599 /* If the host is accepting all local parts, as determined by the "random"
600 check, we don't need to waste time doing any further checking. */
601
602 if (new_domain_record.random_result != ccache_accept && done)
603 {
5417f6d1
PH
604 /* Get the rcpt_include_affixes flag from the transport if there is one,
605 but assume FALSE if there is not. */
606
059ec3d9
PH
607 done =
608 smtp_write_command(&outblock, FALSE, "RCPT TO:<%.1000s>\r\n",
c688b954 609 transport_rcpt_address(addr,
5417f6d1
PH
610 (addr->transport == NULL)? FALSE :
611 addr->transport->rcpt_include_affixes)) >= 0 &&
059ec3d9
PH
612 smtp_read_response(&inblock, responsebuffer, sizeof(responsebuffer),
613 '2', callout);
614
615 if (done)
616 new_address_record.result = ccache_accept;
617 else if (errno == 0 && responsebuffer[0] == '5')
2c7db3f5 618 {
8e669ac1 619 *failure_ptr = US"recipient";
059ec3d9 620 new_address_record.result = ccache_reject;
8e669ac1 621 }
059ec3d9 622
2a4be8f9
PH
623 /* Do postmaster check if requested; if a full check is required, we
624 check for RCPT TO:<postmaster> (no domain) in accordance with RFC 821. */
059ec3d9
PH
625
626 if (done && pm_mailfrom != NULL)
627 {
628 done =
629 smtp_write_command(&outblock, FALSE, "RSET\r\n") >= 0 &&
630 smtp_read_response(&inblock, responsebuffer,
631 sizeof(responsebuffer), '2', callout) &&
632
633 smtp_write_command(&outblock, FALSE,
634 "MAIL FROM:<%s>\r\n", pm_mailfrom) >= 0 &&
635 smtp_read_response(&inblock, responsebuffer,
636 sizeof(responsebuffer), '2', callout) &&
637
2a4be8f9
PH
638 /* First try using the current domain */
639
640 ((
059ec3d9
PH
641 smtp_write_command(&outblock, FALSE,
642 "RCPT TO:<postmaster@%.1000s>\r\n", addr->domain) >= 0 &&
643 smtp_read_response(&inblock, responsebuffer,
2a4be8f9
PH
644 sizeof(responsebuffer), '2', callout)
645 )
646
647 ||
648
649 /* If that doesn't work, and a full check is requested,
650 try without the domain. */
651
652 (
653 (options & vopt_callout_fullpm) != 0 &&
654 smtp_write_command(&outblock, FALSE,
655 "RCPT TO:<postmaster>\r\n") >= 0 &&
656 smtp_read_response(&inblock, responsebuffer,
657 sizeof(responsebuffer), '2', callout)
658 ));
659
660 /* Sort out the cache record */
059ec3d9
PH
661
662 new_domain_record.postmaster_stamp = time(NULL);
663
664 if (done)
665 new_domain_record.postmaster_result = ccache_accept;
666 else if (errno == 0 && responsebuffer[0] == '5')
667 {
8e669ac1 668 *failure_ptr = US"postmaster";
059ec3d9
PH
669 setflag(addr, af_verify_pmfail);
670 new_domain_record.postmaster_result = ccache_reject;
671 }
672 }
673 } /* Random not accepted */
90e9ce59 674 } /* MAIL FROM: accepted */
059ec3d9
PH
675
676 /* For any failure of the main check, other than a negative response, we just
677 close the connection and carry on. We can identify a negative response by the
678 fact that errno is zero. For I/O errors it will be non-zero
679
680 Set up different error texts for logging and for sending back to the caller
681 as an SMTP response. Log in all cases, using a one-line format. For sender
682 callouts, give a full response to the caller, but for recipient callouts,
683 don't give the IP address because this may be an internal host whose identity
684 is not to be widely broadcast. */
685
686 if (!done)
687 {
688 if (errno == ETIMEDOUT)
689 {
690 HDEBUG(D_verify) debug_printf("SMTP timeout\n");
8e669ac1 691 send_quit = FALSE;
059ec3d9
PH
692 }
693 else if (errno == 0)
694 {
695 if (*responsebuffer == 0) Ustrcpy(responsebuffer, US"connection dropped");
696
697 addr->message =
698 string_sprintf("response to \"%s\" from %s [%s] was: %s",
699 big_buffer, host->name, host->address,
700 string_printing(responsebuffer));
701
702 addr->user_message = is_recipient?
703 string_sprintf("Callout verification failed:\n%s", responsebuffer)
704 :
705 string_sprintf("Called: %s\nSent: %s\nResponse: %s",
706 host->address, big_buffer, responsebuffer);
707
708 /* Hard rejection ends the process */
709
710 if (responsebuffer[0] == '5') /* Address rejected */
711 {
712 yield = FAIL;
713 done = TRUE;
714 }
715 }
716 }
717
718 /* End the SMTP conversation and close the connection. */
719
c9bdd01c 720 if (send_quit) (void)smtp_write_command(&outblock, FALSE, "QUIT\r\n");
f1e894f3 721 (void)close(inblock.sock);
059ec3d9
PH
722 } /* Loop through all hosts, while !done */
723
724/* If we get here with done == TRUE, a successful callout happened, and yield
725will be set OK or FAIL according to the response to the RCPT command.
726Otherwise, we looped through the hosts but couldn't complete the business.
727However, there may be domain-specific information to cache in both cases.
728
729The value of the result field in the new_domain record is ccache_unknown if
90e9ce59 730there was an error before or with MAIL FROM:, and errno was not zero,
059ec3d9 731implying some kind of I/O error. We don't want to write the cache in that case.
2b1c6e3a 732Otherwise the value is ccache_accept, ccache_reject, or ccache_reject_mfnull. */
059ec3d9
PH
733
734if (!callout_no_cache && new_domain_record.result != ccache_unknown)
735 {
736 if ((dbm_file = dbfn_open(US"callout", O_RDWR|O_CREAT, &dbblock, FALSE))
737 == NULL)
738 {
739 HDEBUG(D_verify) debug_printf("callout cache: not available\n");
740 }
741 else
742 {
743 (void)dbfn_write(dbm_file, addr->domain, &new_domain_record,
744 (int)sizeof(dbdata_callout_cache));
745 HDEBUG(D_verify) debug_printf("wrote callout cache domain record:\n"
746 " result=%d postmaster=%d random=%d\n",
747 new_domain_record.result,
748 new_domain_record.postmaster_result,
749 new_domain_record.random_result);
750 }
751 }
752
753/* If a definite result was obtained for the callout, cache it unless caching
754is disabled. */
755
756if (done)
757 {
758 if (!callout_no_cache && new_address_record.result != ccache_unknown)
759 {
760 if (dbm_file == NULL)
761 dbm_file = dbfn_open(US"callout", O_RDWR|O_CREAT, &dbblock, FALSE);
762 if (dbm_file == NULL)
763 {
764 HDEBUG(D_verify) debug_printf("no callout cache available\n");
765 }
766 else
767 {
768 (void)dbfn_write(dbm_file, address_key, &new_address_record,
769 (int)sizeof(dbdata_callout_cache_address));
770 HDEBUG(D_verify) debug_printf("wrote %s callout cache address record\n",
771 (new_address_record.result == ccache_accept)? "positive" : "negative");
772 }
773 }
774 } /* done */
775
776/* Failure to connect to any host, or any response other than 2xx or 5xx is a
777temporary error. If there was only one host, and a response was received, leave
778it alone if supplying details. Otherwise, give a generic response. */
779
780else /* !done */
781 {
782 uschar *dullmsg = string_sprintf("Could not complete %s verify callout",
783 is_recipient? "recipient" : "sender");
784 yield = DEFER;
785
786 if (host_list->next != NULL || addr->message == NULL) addr->message = dullmsg;
787
788 addr->user_message = (!smtp_return_error_details)? dullmsg :
789 string_sprintf("%s for <%s>.\n"
790 "The mail server(s) for the domain may be temporarily unreachable, or\n"
791 "they may be permanently unreachable from this server. In the latter case,\n%s",
792 dullmsg, addr->address,
793 is_recipient?
794 "the address will never be accepted."
795 :
796 "you need to change the address or create an MX record for its domain\n"
797 "if it is supposed to be generally accessible from the Internet.\n"
798 "Talk to your mail administrator for details.");
799
800 /* Force a specific error code */
801
802 addr->basic_errno = ERRNO_CALLOUTDEFER;
803 }
804
805/* Come here from within the cache-reading code on fast-track exit. */
806
807END_CALLOUT:
808if (dbm_file != NULL) dbfn_close(dbm_file);
809return yield;
810}
811
812
813
814/*************************************************
815* Copy error to toplevel address *
816*************************************************/
817
818/* This function is used when a verify fails or defers, to ensure that the
819failure or defer information is in the original toplevel address. This applies
820when an address is redirected to a single new address, and the failure or
821deferral happens to the child address.
822
823Arguments:
824 vaddr the verify address item
825 addr the final address item
826 yield FAIL or DEFER
827
828Returns: the value of YIELD
829*/
830
831static int
832copy_error(address_item *vaddr, address_item *addr, int yield)
833{
834if (addr != vaddr)
835 {
836 vaddr->message = addr->message;
837 vaddr->user_message = addr->user_message;
838 vaddr->basic_errno = addr->basic_errno;
839 vaddr->more_errno = addr->more_errno;
b37c4101 840 vaddr->p.address_data = addr->p.address_data;
059ec3d9
PH
841 }
842return yield;
843}
844
845
846
847
848/*************************************************
849* Verify an email address *
850*************************************************/
851
852/* This function is used both for verification (-bv and at other times) and
853address testing (-bt), which is indicated by address_test_mode being set.
854
855Arguments:
856 vaddr contains the address to verify; the next field in this block
857 must be NULL
858 f if not NULL, write the result to this file
859 options various option bits:
860 vopt_fake_sender => this sender verify is not for the real
861 sender (it was verify=sender=xxxx or an address from a
862 header line) - rewriting must not change sender_address
863 vopt_is_recipient => this is a recipient address, otherwise
864 it's a sender address - this affects qualification and
865 rewriting and messages from callouts
866 vopt_qualify => qualify an unqualified address; else error
867 vopt_expn => called from SMTP EXPN command
eafd343b
TK
868 vopt_success_on_redirect => when a new address is generated
869 the verification instantly succeeds
059ec3d9
PH
870
871 These ones are used by do_callout() -- the options variable
872 is passed to it.
873
2a4be8f9 874 vopt_callout_fullpm => if postmaster check, do full one
059ec3d9
PH
875 vopt_callout_no_cache => don't use callout cache
876 vopt_callout_random => do the "random" thing
877 vopt_callout_recipsender => use real sender for recipient
878 vopt_callout_recippmaster => use postmaster for recipient
879
880 callout if > 0, specifies that callout is required, and gives timeout
4deaf07d 881 for individual commands
059ec3d9
PH
882 callout_overall if > 0, gives overall timeout for the callout function;
883 if < 0, a default is used (see do_callout())
8e669ac1 884 callout_connect the connection timeout for callouts
059ec3d9
PH
885 se_mailfrom when callout is requested to verify a sender, use this
886 in MAIL FROM; NULL => ""
887 pm_mailfrom when callout is requested, if non-NULL, do the postmaster
888 thing and use this as the sender address (may be "")
889
890 routed if not NULL, set TRUE if routing succeeded, so we can
891 distinguish between routing failed and callout failed
892
893Returns: OK address verified
894 FAIL address failed to verify
895 DEFER can't tell at present
896*/
897
898int
899verify_address(address_item *vaddr, FILE *f, int options, int callout,
8e669ac1 900 int callout_overall, int callout_connect, uschar *se_mailfrom,
4deaf07d 901 uschar *pm_mailfrom, BOOL *routed)
059ec3d9
PH
902{
903BOOL allok = TRUE;
904BOOL full_info = (f == NULL)? FALSE : (debug_selector != 0);
905BOOL is_recipient = (options & vopt_is_recipient) != 0;
906BOOL expn = (options & vopt_expn) != 0;
eafd343b 907BOOL success_on_redirect = (options & vopt_success_on_redirect) != 0;
059ec3d9
PH
908int i;
909int yield = OK;
910int verify_type = expn? v_expn :
911 address_test_mode? v_none :
912 is_recipient? v_recipient : v_sender;
913address_item *addr_list;
914address_item *addr_new = NULL;
915address_item *addr_remote = NULL;
916address_item *addr_local = NULL;
917address_item *addr_succeed = NULL;
8e669ac1 918uschar **failure_ptr = is_recipient?
2c7db3f5 919 &recipient_verify_failure : &sender_verify_failure;
059ec3d9
PH
920uschar *ko_prefix, *cr;
921uschar *address = vaddr->address;
922uschar *save_sender;
923uschar null_sender[] = { 0 }; /* Ensure writeable memory */
924
2c7db3f5
PH
925/* Clear, just in case */
926
927*failure_ptr = NULL;
928
059ec3d9
PH
929/* Set up a prefix and suffix for error message which allow us to use the same
930output statements both in EXPN mode (where an SMTP response is needed) and when
931debugging with an output file. */
932
933if (expn)
934 {
935 ko_prefix = US"553 ";
936 cr = US"\r";
937 }
938else ko_prefix = cr = US"";
939
940/* Add qualify domain if permitted; otherwise an unqualified address fails. */
941
942if (parse_find_at(address) == NULL)
943 {
944 if ((options & vopt_qualify) == 0)
945 {
946 if (f != NULL)
947 fprintf(f, "%sA domain is required for \"%s\"%s\n", ko_prefix, address,
948 cr);
8e669ac1 949 *failure_ptr = US"qualify";
059ec3d9
PH
950 return FAIL;
951 }
952 address = rewrite_address_qualify(address, is_recipient);
953 }
954
955DEBUG(D_verify)
956 {
957 debug_printf(">>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>\n");
958 debug_printf("%s %s\n", address_test_mode? "Testing" : "Verifying", address);
959 }
960
961/* Rewrite and report on it. Clear the domain and local part caches - these
962may have been set by domains and local part tests during an ACL. */
963
964if (global_rewrite_rules != NULL)
965 {
966 uschar *old = address;
967 address = rewrite_address(address, is_recipient, FALSE,
968 global_rewrite_rules, rewrite_existflags);
969 if (address != old)
970 {
971 for (i = 0; i < (MAX_NAMED_LIST * 2)/32; i++) vaddr->localpart_cache[i] = 0;
972 for (i = 0; i < (MAX_NAMED_LIST * 2)/32; i++) vaddr->domain_cache[i] = 0;
973 if (f != NULL && !expn) fprintf(f, "Address rewritten as: %s\n", address);
974 }
975 }
976
977/* If this is the real sender address, we must update sender_address at
978this point, because it may be referred to in the routers. */
979
980if ((options & (vopt_fake_sender|vopt_is_recipient)) == 0)
981 sender_address = address;
982
983/* If the address was rewritten to <> no verification can be done, and we have
984to return OK. This rewriting is permitted only for sender addresses; for other
985addresses, such rewriting fails. */
986
987if (address[0] == 0) return OK;
988
989/* Save a copy of the sender address for re-instating if we change it to <>
990while verifying a sender address (a nice bit of self-reference there). */
991
992save_sender = sender_address;
993
994/* Update the address structure with the possibly qualified and rewritten
995address. Set it up as the starting address on the chain of new addresses. */
996
997vaddr->address = address;
998addr_new = vaddr;
999
1000/* We need a loop, because an address can generate new addresses. We must also
1001cope with generated pipes and files at the top level. (See also the code and
1002comment in deliver.c.) However, it is usually the case that the router for
1003user's .forward files has its verify flag turned off.
1004
1005If an address generates more than one child, the loop is used only when
1006full_info is set, and this can only be set locally. Remote enquiries just get
1007information about the top level address, not anything that it generated. */
1008
1009while (addr_new != NULL)
1010 {
1011 int rc;
e6f6568e 1012 uschar *show_address;
059ec3d9
PH
1013 address_item *addr = addr_new;
1014
1015 addr_new = addr->next;
1016 addr->next = NULL;
1017
e6f6568e
PH
1018 /* When full_info is set, child addresses are displayed in top-level
1019 messages. Otherwise, we show only the top level address. */
1020
1021 show_address = full_info? addr->address : address;
1022
059ec3d9
PH
1023 DEBUG(D_verify)
1024 {
1025 debug_printf(">>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>\n");
1026 debug_printf("Considering %s\n", addr->address);
1027 }
1028
1029 /* Handle generated pipe, file or reply addresses. We don't get these
1030 when handling EXPN, as it does only one level of expansion. */
1031
1032 if (testflag(addr, af_pfr))
1033 {
1034 allok = FALSE;
1035 if (f != NULL)
1036 {
1037 BOOL allow;
1038
1039 if (addr->address[0] == '>')
1040 {
1041 allow = testflag(addr, af_allow_reply);
1042 fprintf(f, "%s -> mail %s", addr->parent->address, addr->address + 1);
1043 }
1044 else
1045 {
1046 allow = (addr->address[0] == '|')?
1047 testflag(addr, af_allow_pipe) : testflag(addr, af_allow_file);
1048 fprintf(f, "%s -> %s", addr->parent->address, addr->address);
1049 }
1050
1051 if (addr->basic_errno == ERRNO_BADTRANSPORT)
1052 fprintf(f, "\n*** Error in setting up pipe, file, or autoreply:\n"
1053 "%s\n", addr->message);
1054 else if (allow)
1055 fprintf(f, "\n transport = %s\n", addr->transport->name);
1056 else
1057 fprintf(f, " *** forbidden ***\n");
1058 }
1059 continue;
1060 }
1061
1062 /* Just in case some router parameter refers to it. */
1063
1064 return_path = (addr->p.errors_address != NULL)?
1065 addr->p.errors_address : sender_address;
1066
1067 /* Split the address into domain and local part, handling the %-hack if
1068 necessary, and then route it. While routing a sender address, set
1069 $sender_address to <> because that is what it will be if we were trying to
1070 send a bounce to the sender. */
1071
1072 if (routed != NULL) *routed = FALSE;
1073 if ((rc = deliver_split_address(addr)) == OK)
1074 {
1075 if (!is_recipient) sender_address = null_sender;
1076 rc = route_address(addr, &addr_local, &addr_remote, &addr_new,
1077 &addr_succeed, verify_type);
1078 sender_address = save_sender; /* Put back the real sender */
1079 }
1080
1081 /* If routing an address succeeded, set the flag that remembers, for use when
1082 an ACL cached a sender verify (in case a callout fails). Then if routing set
1083 up a list of hosts or the transport has a host list, and the callout option
1084 is set, and we aren't in a host checking run, do the callout verification,
1085 and set another flag that notes that a callout happened. */
1086
1087 if (rc == OK)
1088 {
1089 if (routed != NULL) *routed = TRUE;
1090 if (callout > 0)
1091 {
1092 host_item *host_list = addr->host_list;
1093
26da7e20
PH
1094 /* Make up some data for use in the case where there is no remote
1095 transport. */
1096
1097 transport_feedback tf = {
1098 NULL, /* interface (=> any) */
1099 US"smtp", /* port */
1100 US"smtp", /* protocol */
1101 NULL, /* hosts */
1102 US"$smtp_active_hostname", /* helo_data */
1103 FALSE, /* hosts_override */
1104 FALSE, /* hosts_randomize */
1105 FALSE, /* gethostbyname */
1106 TRUE, /* qualify_single */
1107 FALSE /* search_parents */
1108 };
059ec3d9
PH
1109
1110 /* If verification yielded a remote transport, we want to use that
1111 transport's options, so as to mimic what would happen if we were really
1112 sending a message to this address. */
1113
1114 if (addr->transport != NULL && !addr->transport->info->local)
1115 {
929ba01c 1116 (void)(addr->transport->setup)(addr->transport, addr, &tf, 0, 0, NULL);
059ec3d9
PH
1117
1118 /* If the transport has hosts and the router does not, or if the
1119 transport is configured to override the router's hosts, we must build a
1120 host list of the transport's hosts, and find the IP addresses */
1121
1122 if (tf.hosts != NULL && (host_list == NULL || tf.hosts_override))
1123 {
1124 uschar *s;
750af86e
PH
1125 uschar *save_deliver_domain = deliver_domain;
1126 uschar *save_deliver_localpart = deliver_localpart;
059ec3d9
PH
1127
1128 host_list = NULL; /* Ignore the router's hosts */
1129
1130 deliver_domain = addr->domain;
1131 deliver_localpart = addr->local_part;
1132 s = expand_string(tf.hosts);
750af86e
PH
1133 deliver_domain = save_deliver_domain;
1134 deliver_localpart = save_deliver_localpart;
059ec3d9
PH
1135
1136 if (s == NULL)
1137 {
1138 log_write(0, LOG_MAIN|LOG_PANIC, "failed to expand list of hosts "
1139 "\"%s\" in %s transport for callout: %s", tf.hosts,
1140 addr->transport->name, expand_string_message);
1141 }
1142 else
1143 {
1144 uschar *canonical_name;
d8ef3577 1145 host_item *host, *nexthost;
059ec3d9
PH
1146 host_build_hostlist(&host_list, s, tf.hosts_randomize);
1147
1148 /* Just ignore failures to find a host address. If we don't manage
8e669ac1
PH
1149 to find any addresses, the callout will defer. Note that more than
1150 one address may be found for a single host, which will result in
1151 additional host items being inserted into the chain. Hence we must
d8ef3577 1152 save the next host first. */
059ec3d9 1153
d8ef3577 1154 for (host = host_list; host != NULL; host = nexthost)
059ec3d9 1155 {
d8ef3577 1156 nexthost = host->next;
8e669ac1 1157 if (tf.gethostbyname ||
7e66e54d 1158 string_is_ip_address(host->name, NULL) != 0)
059ec3d9
PH
1159 (void)host_find_byname(host, NULL, &canonical_name, TRUE);
1160 else
1161 {
1162 int flags = HOST_FIND_BY_A;
1163 if (tf.qualify_single) flags |= HOST_FIND_QUALIFY_SINGLE;
1164 if (tf.search_parents) flags |= HOST_FIND_SEARCH_PARENTS;
1165 (void)host_find_bydns(host, NULL, flags, NULL, NULL, NULL,
1166 &canonical_name, NULL);
1167 }
1168 }
1169 }
1170 }
1171 }
1172
8e669ac1 1173 /* Can only do a callout if we have at least one host! If the callout
2c7db3f5 1174 fails, it will have set ${sender,recipient}_verify_failure. */
059ec3d9
PH
1175
1176 if (host_list != NULL)
1177 {
1178 HDEBUG(D_verify) debug_printf("Attempting full verification using callout\n");
1179 if (host_checking && !host_checking_callout)
1180 {
1181 HDEBUG(D_verify)
1182 debug_printf("... callout omitted by default when host testing\n"
1183 "(Use -bhc if you want the callouts to happen.)\n");
1184 }
1185 else
1186 {
1187 rc = do_callout(addr, host_list, &tf, callout, callout_overall,
4deaf07d 1188 callout_connect, options, se_mailfrom, pm_mailfrom);
059ec3d9
PH
1189 }
1190 }
1191 else
1192 {
1193 HDEBUG(D_verify) debug_printf("Cannot do callout: neither router nor "
1194 "transport provided a host list\n");
1195 }
1196 }
1197 }
8e669ac1 1198
2c7db3f5 1199 /* Otherwise, any failure is a routing failure */
8e669ac1
PH
1200
1201 else *failure_ptr = US"route";
059ec3d9
PH
1202
1203 /* A router may return REROUTED if it has set up a child address as a result
1204 of a change of domain name (typically from widening). In this case we always
1205 want to continue to verify the new child. */
1206
1207 if (rc == REROUTED) continue;
8e669ac1 1208
059ec3d9
PH
1209 /* Handle hard failures */
1210
1211 if (rc == FAIL)
1212 {
1213 allok = FALSE;
1214 if (f != NULL)
1215 {
e6f6568e
PH
1216 address_item *p = addr->parent;
1217
1218 fprintf(f, "%s%s %s", ko_prefix, show_address,
059ec3d9
PH
1219 address_test_mode? "is undeliverable" : "failed to verify");
1220 if (!expn && admin_user)
1221 {
1222 if (addr->basic_errno > 0)
1223 fprintf(f, ": %s", strerror(addr->basic_errno));
1224 if (addr->message != NULL)
e6f6568e
PH
1225 fprintf(f, ": %s", addr->message);
1226 }
1227
1228 /* Show parents iff doing full info */
1229
1230 if (full_info) while (p != NULL)
1231 {
1232 fprintf(f, "%s\n <-- %s", cr, p->address);
1233 p = p->parent;
059ec3d9
PH
1234 }
1235 fprintf(f, "%s\n", cr);
1236 }
1237
1238 if (!full_info) return copy_error(vaddr, addr, FAIL);
1239 else yield = FAIL;
1240 }
1241
1242 /* Soft failure */
1243
1244 else if (rc == DEFER)
1245 {
1246 allok = FALSE;
1247 if (f != NULL)
1248 {
e6f6568e
PH
1249 address_item *p = addr->parent;
1250 fprintf(f, "%s%s cannot be resolved at this time", ko_prefix,
1251 show_address);
059ec3d9
PH
1252 if (!expn && admin_user)
1253 {
1254 if (addr->basic_errno > 0)
e6f6568e 1255 fprintf(f, ": %s", strerror(addr->basic_errno));
059ec3d9 1256 if (addr->message != NULL)
e6f6568e 1257 fprintf(f, ": %s", addr->message);
059ec3d9 1258 else if (addr->basic_errno <= 0)
e6f6568e 1259 fprintf(f, ": unknown error");
059ec3d9
PH
1260 }
1261
e6f6568e
PH
1262 /* Show parents iff doing full info */
1263
1264 if (full_info) while (p != NULL)
1265 {
1266 fprintf(f, "%s\n <-- %s", cr, p->address);
1267 p = p->parent;
1268 }
059ec3d9
PH
1269 fprintf(f, "%s\n", cr);
1270 }
e6f6568e 1271
059ec3d9
PH
1272 if (!full_info) return copy_error(vaddr, addr, DEFER);
1273 else if (yield == OK) yield = DEFER;
1274 }
1275
1276 /* If we are handling EXPN, we do not want to continue to route beyond
e6f6568e 1277 the top level (whose address is in "address"). */
059ec3d9
PH
1278
1279 else if (expn)
1280 {
1281 uschar *ok_prefix = US"250-";
1282 if (addr_new == NULL)
1283 {
1284 if (addr_local == NULL && addr_remote == NULL)
1285 fprintf(f, "250 mail to <%s> is discarded\r\n", address);
1286 else
1287 fprintf(f, "250 <%s>\r\n", address);
1288 }
1289 else while (addr_new != NULL)
1290 {
1291 address_item *addr2 = addr_new;
1292 addr_new = addr2->next;
1293 if (addr_new == NULL) ok_prefix = US"250 ";
1294 fprintf(f, "%s<%s>\r\n", ok_prefix, addr2->address);
1295 }
1296 return OK;
1297 }
1298
1299 /* Successful routing other than EXPN. */
1300
1301 else
1302 {
1303 /* Handle successful routing when short info wanted. Otherwise continue for
1304 other (generated) addresses. Short info is the operational case. Full info
1305 can be requested only when debug_selector != 0 and a file is supplied.
1306
1307 There is a conflict between the use of aliasing as an alternate email
1308 address, and as a sort of mailing list. If an alias turns the incoming
1309 address into just one address (e.g. J.Caesar->jc44) you may well want to
1310 carry on verifying the generated address to ensure it is valid when
1311 checking incoming mail. If aliasing generates multiple addresses, you
1312 probably don't want to do this. Exim therefore treats the generation of
1313 just a single new address as a special case, and continues on to verify the
1314 generated address. */
1315
1316 if (!full_info && /* Stop if short info wanted AND */
eafd343b
TK
1317 (((addr_new == NULL || /* No new address OR */
1318 addr_new->next != NULL || /* More than one new address OR */
1319 testflag(addr_new, af_pfr))) /* New address is pfr */
1320 || /* OR */
1321 (addr_new != NULL && /* At least one new address AND */
1322 success_on_redirect))) /* success_on_redirect is set */
059ec3d9 1323 {
e6f6568e 1324 if (f != NULL) fprintf(f, "%s %s\n", show_address,
059ec3d9
PH
1325 address_test_mode? "is deliverable" : "verified");
1326
1327 /* If we have carried on to verify a child address, we want the value
1328 of $address_data to be that of the child */
1329
1330 vaddr->p.address_data = addr->p.address_data;
1331 return OK;
1332 }
1333 }
1334 } /* Loop for generated addresses */
1335
1336/* Display the full results of the successful routing, including any generated
1337addresses. Control gets here only when full_info is set, which requires f not
1338to be NULL, and this occurs only when a top-level verify is called with the
1339debugging switch on.
1340
1341If there are no local and no remote addresses, and there were no pipes, files,
1342or autoreplies, and there were no errors or deferments, the message is to be
1343discarded, usually because of the use of :blackhole: in an alias file. */
1344
1345if (allok && addr_local == NULL && addr_remote == NULL)
dbcef0ea 1346 {
059ec3d9 1347 fprintf(f, "mail to %s is discarded\n", address);
dbcef0ea
PH
1348 return yield;
1349 }
059ec3d9 1350
dbcef0ea 1351for (addr_list = addr_local, i = 0; i < 2; addr_list = addr_remote, i++)
059ec3d9
PH
1352 {
1353 while (addr_list != NULL)
1354 {
1355 address_item *addr = addr_list;
1356 address_item *p = addr->parent;
1357 addr_list = addr->next;
1358
1359 fprintf(f, "%s", CS addr->address);
384152a6
TK
1360#ifdef EXPERIMENTAL_SRS
1361 if(addr->p.srs_sender)
1362 fprintf(f, " [srs = %s]", addr->p.srs_sender);
1363#endif
dbcef0ea
PH
1364
1365 /* If the address is a duplicate, show something about it. */
1366
1367 if (!testflag(addr, af_pfr))
1368 {
1369 tree_node *tnode;
1370 if ((tnode = tree_search(tree_duplicates, addr->unique)) != NULL)
1371 fprintf(f, " [duplicate, would not be delivered]");
1372 else tree_add_duplicate(addr->unique, addr);
1373 }
1374
1375 /* Now show its parents */
1376
059ec3d9
PH
1377 while (p != NULL)
1378 {
1379 fprintf(f, "\n <-- %s", p->address);
1380 p = p->parent;
1381 }
1382 fprintf(f, "\n ");
1383
1384 /* Show router, and transport */
1385
1386 fprintf(f, "router = %s, ", addr->router->name);
1387 fprintf(f, "transport = %s\n", (addr->transport == NULL)? US"unset" :
1388 addr->transport->name);
1389
1390 /* Show any hosts that are set up by a router unless the transport
1391 is going to override them; fiddle a bit to get a nice format. */
1392
1393 if (addr->host_list != NULL && addr->transport != NULL &&
1394 !addr->transport->overrides_hosts)
1395 {
1396 host_item *h;
1397 int maxlen = 0;
1398 int maxaddlen = 0;
1399 for (h = addr->host_list; h != NULL; h = h->next)
1400 {
1401 int len = Ustrlen(h->name);
1402 if (len > maxlen) maxlen = len;
1403 len = (h->address != NULL)? Ustrlen(h->address) : 7;
1404 if (len > maxaddlen) maxaddlen = len;
1405 }
1406 for (h = addr->host_list; h != NULL; h = h->next)
1407 {
1408 int len = Ustrlen(h->name);
1409 fprintf(f, " host %s ", h->name);
1410 while (len++ < maxlen) fprintf(f, " ");
1411 if (h->address != NULL)
1412 {
1413 fprintf(f, "[%s] ", h->address);
1414 len = Ustrlen(h->address);
1415 }
1416 else if (!addr->transport->info->local) /* Omit [unknown] for local */
1417 {
1418 fprintf(f, "[unknown] ");
1419 len = 7;
1420 }
1421 else len = -3;
1422 while (len++ < maxaddlen) fprintf(f," ");
1423 if (h->mx >= 0) fprintf(f, "MX=%d", h->mx);
1424 if (h->port != PORT_NONE) fprintf(f, " port=%d", h->port);
1425 if (h->status == hstatus_unusable) fprintf(f, " ** unusable **");
1426 fprintf(f, "\n");
1427 }
1428 }
1429 }
1430 }
1431
8e669ac1 1432/* Will be DEFER or FAIL if any one address has, only for full_info (which is
2c7db3f5
PH
1433the -bv or -bt case). */
1434
8e669ac1 1435return yield;
059ec3d9
PH
1436}
1437
1438
1439
1440
1441/*************************************************
1442* Check headers for syntax errors *
1443*************************************************/
1444
1445/* This function checks those header lines that contain addresses, and verifies
1446that all the addresses therein are syntactially correct.
1447
1448Arguments:
1449 msgptr where to put an error message
1450
1451Returns: OK
1452 FAIL
1453*/
1454
1455int
1456verify_check_headers(uschar **msgptr)
1457{
1458header_line *h;
1459uschar *colon, *s;
1460
1461for (h = header_list; h != NULL; h = h->next)
1462 {
1463 if (h->type != htype_from &&
1464 h->type != htype_reply_to &&
1465 h->type != htype_sender &&
1466 h->type != htype_to &&
1467 h->type != htype_cc &&
1468 h->type != htype_bcc)
1469 continue;
1470
1471 colon = Ustrchr(h->text, ':');
1472 s = colon + 1;
1473 while (isspace(*s)) s++;
1474
1475 parse_allow_group = TRUE; /* Allow group syntax */
1476
1477 /* Loop for multiple addresses in the header */
1478
1479 while (*s != 0)
1480 {
1481 uschar *ss = parse_find_address_end(s, FALSE);
1482 uschar *recipient, *errmess;
1483 int terminator = *ss;
1484 int start, end, domain;
1485
1486 /* Temporarily terminate the string at this point, and extract the
1487 operative address within. */
1488
1489 *ss = 0;
1490 recipient = parse_extract_address(s,&errmess,&start,&end,&domain,FALSE);
1491 *ss = terminator;
1492
1493 /* Permit an unqualified address only if the message is local, or if the
1494 sending host is configured to be permitted to send them. */
1495
1496 if (recipient != NULL && domain == 0)
1497 {
1498 if (h->type == htype_from || h->type == htype_sender)
1499 {
1500 if (!allow_unqualified_sender) recipient = NULL;
1501 }
1502 else
1503 {
1504 if (!allow_unqualified_recipient) recipient = NULL;
1505 }
1506 if (recipient == NULL) errmess = US"unqualified address not permitted";
1507 }
1508
1509 /* It's an error if no address could be extracted, except for the special
1510 case of an empty address. */
1511
1512 if (recipient == NULL && Ustrcmp(errmess, "empty address") != 0)
1513 {
1514 uschar *verb = US"is";
1515 uschar *t = ss;
1ab95fa6 1516 uschar *tt = colon;
059ec3d9
PH
1517 int len;
1518
1519 /* Arrange not to include any white space at the end in the
1ab95fa6 1520 error message or the header name. */
059ec3d9
PH
1521
1522 while (t > s && isspace(t[-1])) t--;
1ab95fa6 1523 while (tt > h->text && isspace(tt[-1])) tt--;
059ec3d9 1524
1ab95fa6 1525 /* Add the address that failed to the error message, since in a
059ec3d9
PH
1526 header with very many addresses it is sometimes hard to spot
1527 which one is at fault. However, limit the amount of address to
1528 quote - cases have been seen where, for example, a missing double
1529 quote in a humungous To: header creates an "address" that is longer
1530 than string_sprintf can handle. */
1531
1532 len = t - s;
1533 if (len > 1024)
1534 {
1535 len = 1024;
1536 verb = US"begins";
1537 }
1538
1539 *msgptr = string_printing(
1ab95fa6
PH
1540 string_sprintf("%s: failing address in \"%.*s:\" header %s: %.*s",
1541 errmess, tt - h->text, h->text, verb, len, s));
059ec3d9
PH
1542
1543 return FAIL;
1544 }
1545
1546 /* Advance to the next address */
1547
1548 s = ss + (terminator? 1:0);
1549 while (isspace(*s)) s++;
1550 } /* Next address */
1551 } /* Next header */
1552
1553return OK;
1554}
1555
1556
1557
1c41c9cc
PH
1558/*************************************************
1559* Check for blind recipients *
1560*************************************************/
1561
1562/* This function checks that every (envelope) recipient is mentioned in either
1563the To: or Cc: header lines, thus detecting blind carbon copies.
1564
1565There are two ways of scanning that could be used: either scan the header lines
1566and tick off the recipients, or scan the recipients and check the header lines.
1567The original proposed patch did the former, but I have chosen to do the latter,
1568because (a) it requires no memory and (b) will use fewer resources when there
1569are many addresses in To: and/or Cc: and only one or two envelope recipients.
1570
1571Arguments: none
1572Returns: OK if there are no blind recipients
1573 FAIL if there is at least one blind recipient
1574*/
1575
1576int
1577verify_check_notblind(void)
1578{
1579int i;
1580for (i = 0; i < recipients_count; i++)
1581 {
1582 header_line *h;
1583 BOOL found = FALSE;
1584 uschar *address = recipients_list[i].address;
1585
1586 for (h = header_list; !found && h != NULL; h = h->next)
1587 {
1588 uschar *colon, *s;
1589
1590 if (h->type != htype_to && h->type != htype_cc) continue;
1591
1592 colon = Ustrchr(h->text, ':');
1593 s = colon + 1;
1594 while (isspace(*s)) s++;
1595
1596 parse_allow_group = TRUE; /* Allow group syntax */
1597
1598 /* Loop for multiple addresses in the header */
1599
1600 while (*s != 0)
1601 {
1602 uschar *ss = parse_find_address_end(s, FALSE);
1603 uschar *recipient,*errmess;
1604 int terminator = *ss;
1605 int start, end, domain;
1606
1607 /* Temporarily terminate the string at this point, and extract the
1608 operative address within. */
1609
1610 *ss = 0;
1611 recipient = parse_extract_address(s,&errmess,&start,&end,&domain,FALSE);
1612 *ss = terminator;
1613
1614 /* If we found a valid recipient that has a domain, compare it with the
1615 envelope recipient. Local parts are compared case-sensitively, domains
1616 case-insensitively. By comparing from the start with length "domain", we
1617 include the "@" at the end, which ensures that we are comparing the whole
1618 local part of each address. */
1619
1620 if (recipient != NULL && domain != 0)
1621 {
1622 found = Ustrncmp(recipient, address, domain) == 0 &&
1623 strcmpic(recipient + domain, address + domain) == 0;
1624 if (found) break;
1625 }
1626
1627 /* Advance to the next address */
1628
1629 s = ss + (terminator? 1:0);
1630 while (isspace(*s)) s++;
1631 } /* Next address */
1632 } /* Next header (if found is false) */
1633
1634 if (!found) return FAIL;
1635 } /* Next recipient */
1636
1637return OK;
1638}
1639
1640
059ec3d9
PH
1641
1642/*************************************************
1643* Find if verified sender *
1644*************************************************/
1645
1646/* Usually, just a single address is verified as the sender of the message.
1647However, Exim can be made to verify other addresses as well (often related in
1648some way), and this is useful in some environments. There may therefore be a
1649chain of such addresses that have previously been tested. This function finds
1650whether a given address is on the chain.
1651
1652Arguments: the address to be verified
1653Returns: pointer to an address item, or NULL
1654*/
1655
1656address_item *
1657verify_checked_sender(uschar *sender)
1658{
1659address_item *addr;
1660for (addr = sender_verified_list; addr != NULL; addr = addr->next)
1661 if (Ustrcmp(sender, addr->address) == 0) break;
1662return addr;
1663}
1664
1665
1666
1667
1668
1669/*************************************************
1670* Get valid header address *
1671*************************************************/
1672
1673/* Scan the originator headers of the message, looking for an address that
1674verifies successfully. RFC 822 says:
1675
1676 o The "Sender" field mailbox should be sent notices of
1677 any problems in transport or delivery of the original
1678 messages. If there is no "Sender" field, then the
1679 "From" field mailbox should be used.
1680
1681 o If the "Reply-To" field exists, then the reply should
1682 go to the addresses indicated in that field and not to
1683 the address(es) indicated in the "From" field.
1684
1685So we check a Sender field if there is one, else a Reply_to field, else a From
1686field. As some strange messages may have more than one of these fields,
1687especially if they are resent- fields, check all of them if there is more than
1688one.
1689
1690Arguments:
1691 user_msgptr points to where to put a user error message
1692 log_msgptr points to where to put a log error message
1693 callout timeout for callout check (passed to verify_address())
1694 callout_overall overall callout timeout (ditto)
8e669ac1 1695 callout_connect connect callout timeout (ditto)
059ec3d9
PH
1696 se_mailfrom mailfrom for verify; NULL => ""
1697 pm_mailfrom sender for pm callout check (passed to verify_address())
1698 options callout options (passed to verify_address())
8e669ac1 1699 verrno where to put the address basic_errno
059ec3d9
PH
1700
1701If log_msgptr is set to something without setting user_msgptr, the caller
1702normally uses log_msgptr for both things.
1703
1704Returns: result of the verification attempt: OK, FAIL, or DEFER;
1705 FAIL is given if no appropriate headers are found
1706*/
1707
1708int
1709verify_check_header_address(uschar **user_msgptr, uschar **log_msgptr,
8e669ac1 1710 int callout, int callout_overall, int callout_connect, uschar *se_mailfrom,
fe5b5d0b 1711 uschar *pm_mailfrom, int options, int *verrno)
059ec3d9
PH
1712{
1713static int header_types[] = { htype_sender, htype_reply_to, htype_from };
1714int yield = FAIL;
1715int i;
1716
1717for (i = 0; i < 3; i++)
1718 {
1719 header_line *h;
1720 for (h = header_list; h != NULL; h = h->next)
1721 {
1722 int terminator, new_ok;
1723 uschar *s, *ss, *endname;
1724
1725 if (h->type != header_types[i]) continue;
1726 s = endname = Ustrchr(h->text, ':') + 1;
1727
1728 while (*s != 0)
1729 {
1730 address_item *vaddr;
1731
1732 while (isspace(*s) || *s == ',') s++;
1733 if (*s == 0) break; /* End of header */
1734
1735 ss = parse_find_address_end(s, FALSE);
1736
1737 /* The terminator is a comma or end of header, but there may be white
1738 space preceding it (including newline for the last address). Move back
1739 past any white space so we can check against any cached envelope sender
1740 address verifications. */
1741
1742 while (isspace(ss[-1])) ss--;
1743 terminator = *ss;
1744 *ss = 0;
1745
1746 HDEBUG(D_verify) debug_printf("verifying %.*s header address %s\n",
1747 (int)(endname - h->text), h->text, s);
1748
1749 /* See if we have already verified this address as an envelope sender,
1750 and if so, use the previous answer. */
1751
1752 vaddr = verify_checked_sender(s);
1753
1754 if (vaddr != NULL && /* Previously checked */
1755 (callout <= 0 || /* No callout needed; OR */
1756 vaddr->special_action > 256)) /* Callout was done */
1757 {
1758 new_ok = vaddr->special_action & 255;
1759 HDEBUG(D_verify) debug_printf("previously checked as envelope sender\n");
1760 *ss = terminator; /* Restore shortened string */
1761 }
1762
1763 /* Otherwise we run the verification now. We must restore the shortened
1764 string before running the verification, so the headers are correct, in
1765 case there is any rewriting. */
1766
1767 else
1768 {
1769 int start, end, domain;
1770 uschar *address = parse_extract_address(s, log_msgptr, &start,
1771 &end, &domain, FALSE);
1772
1773 *ss = terminator;
1774
1775 /* If verification failed because of a syntax error, fail this
1776 function, and ensure that the failing address gets added to the error
1777 message. */
1778
1779 if (address == NULL)
1780 {
1781 new_ok = FAIL;
1782 if (*log_msgptr != NULL)
1783 {
1784 while (ss > s && isspace(ss[-1])) ss--;
1785 *log_msgptr = string_sprintf("syntax error in '%.*s' header when "
1786 "scanning for sender: %s in \"%.*s\"",
1787 endname - h->text, h->text, *log_msgptr, ss - s, s);
1788 return FAIL;
1789 }
1790 }
1791
2f6603e1 1792 /* Else go ahead with the sender verification. But it isn't *the*
059ec3d9
PH
1793 sender of the message, so set vopt_fake_sender to stop sender_address
1794 being replaced after rewriting or qualification. */
1795
1796 else
1797 {
1798 vaddr = deliver_make_addr(address, FALSE);
1799 new_ok = verify_address(vaddr, NULL, options | vopt_fake_sender,
8e669ac1 1800 callout, callout_overall, callout_connect, se_mailfrom,
4deaf07d 1801 pm_mailfrom, NULL);
059ec3d9
PH
1802 }
1803 }
1804
1805 /* We now have the result, either newly found, or cached. If we are
1806 giving out error details, set a specific user error. This means that the
1807 last of these will be returned to the user if all three fail. We do not
1808 set a log message - the generic one below will be used. */
1809
fe5b5d0b 1810 if (new_ok != OK)
059ec3d9 1811 {
8e669ac1 1812 *verrno = vaddr->basic_errno;
fe5b5d0b
PH
1813 if (smtp_return_error_details)
1814 {
1815 *user_msgptr = string_sprintf("Rejected after DATA: "
1816 "could not verify \"%.*s\" header address\n%s: %s",
1817 endname - h->text, h->text, vaddr->address, vaddr->message);
1818 }
8e669ac1 1819 }
059ec3d9
PH
1820
1821 /* Success or defer */
1822
1823 if (new_ok == OK) return OK;
1824 if (new_ok == DEFER) yield = DEFER;
1825
1826 /* Move on to any more addresses in the header */
1827
1828 s = ss;
1829 }
1830 }
1831 }
1832
1833if (yield == FAIL && *log_msgptr == NULL)
1834 *log_msgptr = US"there is no valid sender in any header line";
1835
1836if (yield == DEFER && *log_msgptr == NULL)
1837 *log_msgptr = US"all attempts to verify a sender in a header line deferred";
1838
1839return yield;
1840}
1841
1842
1843
1844
1845/*************************************************
1846* Get RFC 1413 identification *
1847*************************************************/
1848
1849/* Attempt to get an id from the sending machine via the RFC 1413 protocol. If
1850the timeout is set to zero, then the query is not done. There may also be lists
1851of hosts and nets which are exempt. To guard against malefactors sending
1852non-printing characters which could, for example, disrupt a message's headers,
1853make sure the string consists of printing characters only.
1854
1855Argument:
1856 port the port to connect to; usually this is IDENT_PORT (113), but when
1857 running in the test harness with -bh a different value is used.
1858
1859Returns: nothing
1860
1861Side effect: any received ident value is put in sender_ident (NULL otherwise)
1862*/
1863
1864void
1865verify_get_ident(int port)
1866{
1867int sock, host_af, qlen;
1868int received_sender_port, received_interface_port, n;
1869uschar *p;
1870uschar buffer[2048];
1871
1872/* Default is no ident. Check whether we want to do an ident check for this
1873host. */
1874
1875sender_ident = NULL;
1876if (rfc1413_query_timeout <= 0 || verify_check_host(&rfc1413_hosts) != OK)
1877 return;
1878
1879DEBUG(D_ident) debug_printf("doing ident callback\n");
1880
1881/* Set up a connection to the ident port of the remote host. Bind the local end
1882to the incoming interface address. If the sender host address is an IPv6
1883address, the incoming interface address will also be IPv6. */
1884
1885host_af = (Ustrchr(sender_host_address, ':') == NULL)? AF_INET : AF_INET6;
1886sock = ip_socket(SOCK_STREAM, host_af);
1887if (sock < 0) return;
1888
1889if (ip_bind(sock, host_af, interface_address, 0) < 0)
1890 {
1891 DEBUG(D_ident) debug_printf("bind socket for ident failed: %s\n",
1892 strerror(errno));
1893 goto END_OFF;
1894 }
1895
1896if (ip_connect(sock, host_af, sender_host_address, port, rfc1413_query_timeout)
1897 < 0)
1898 {
1899 if (errno == ETIMEDOUT && (log_extra_selector & LX_ident_timeout) != 0)
1900 {
1901 log_write(0, LOG_MAIN, "ident connection to %s timed out",
1902 sender_host_address);
1903 }
1904 else
1905 {
1906 DEBUG(D_ident) debug_printf("ident connection to %s failed: %s\n",
1907 sender_host_address, strerror(errno));
1908 }
1909 goto END_OFF;
1910 }
1911
1912/* Construct and send the query. */
1913
1914sprintf(CS buffer, "%d , %d\r\n", sender_host_port, interface_port);
1915qlen = Ustrlen(buffer);
1916if (send(sock, buffer, qlen, 0) < 0)
1917 {
1918 DEBUG(D_ident) debug_printf("ident send failed: %s\n", strerror(errno));
1919 goto END_OFF;
1920 }
1921
1922/* Read a response line. We put it into the rest of the buffer, using several
1923recv() calls if necessary. */
1924
1925p = buffer + qlen;
1926
1927for (;;)
1928 {
1929 uschar *pp;
1930 int count;
1931 int size = sizeof(buffer) - (p - buffer);
1932
1933 if (size <= 0) goto END_OFF; /* Buffer filled without seeing \n. */
1934 count = ip_recv(sock, p, size, rfc1413_query_timeout);
1935 if (count <= 0) goto END_OFF; /* Read error or EOF */
1936
1937 /* Scan what we just read, to see if we have reached the terminating \r\n. Be
1938 generous, and accept a plain \n terminator as well. The only illegal
1939 character is 0. */
1940
1941 for (pp = p; pp < p + count; pp++)
1942 {
1943 if (*pp == 0) goto END_OFF; /* Zero octet not allowed */
1944 if (*pp == '\n')
1945 {
1946 if (pp[-1] == '\r') pp--;
1947 *pp = 0;
1948 goto GOT_DATA; /* Break out of both loops */
1949 }
1950 }
1951
1952 /* Reached the end of the data without finding \n. Let the loop continue to
1953 read some more, if there is room. */
1954
1955 p = pp;
1956 }
1957
1958GOT_DATA:
1959
1960/* We have received a line of data. Check it carefully. It must start with the
1961same two port numbers that we sent, followed by data as defined by the RFC. For
1962example,
1963
1964 12345 , 25 : USERID : UNIX :root
1965
1966However, the amount of white space may be different to what we sent. In the
1967"osname" field there may be several sub-fields, comma separated. The data we
1968actually want to save follows the third colon. Some systems put leading spaces
1969in it - we discard those. */
1970
1971if (sscanf(CS buffer + qlen, "%d , %d%n", &received_sender_port,
1972 &received_interface_port, &n) != 2 ||
1973 received_sender_port != sender_host_port ||
1974 received_interface_port != interface_port)
1975 goto END_OFF;
1976
1977p = buffer + qlen + n;
1978while(isspace(*p)) p++;
1979if (*p++ != ':') goto END_OFF;
1980while(isspace(*p)) p++;
1981if (Ustrncmp(p, "USERID", 6) != 0) goto END_OFF;
1982p += 6;
1983while(isspace(*p)) p++;
1984if (*p++ != ':') goto END_OFF;
1985while (*p != 0 && *p != ':') p++;
1986if (*p++ == 0) goto END_OFF;
1987while(isspace(*p)) p++;
1988if (*p == 0) goto END_OFF;
1989
1990/* The rest of the line is the data we want. We turn it into printing
1991characters when we save it, so that it cannot mess up the format of any logging
1992or Received: lines into which it gets inserted. We keep a maximum of 127
1993characters. */
1994
1995sender_ident = string_printing(string_copyn(p, 127));
1996DEBUG(D_ident) debug_printf("sender_ident = %s\n", sender_ident);
1997
1998END_OFF:
f1e894f3 1999(void)close(sock);
059ec3d9
PH
2000return;
2001}
2002
2003
2004
2005
2006/*************************************************
2007* Match host to a single host-list item *
2008*************************************************/
2009
2010/* This function compares a host (name or address) against a single item
2011from a host list. The host name gets looked up if it is needed and is not
2012already known. The function is called from verify_check_this_host() via
2013match_check_list(), which is why most of its arguments are in a single block.
2014
2015Arguments:
2016 arg the argument block (see below)
2017 ss the host-list item
2018 valueptr where to pass back looked up data, or NULL
2019 error for error message when returning ERROR
2020
2021The block contains:
32d668a5
PH
2022 host_name (a) the host name, or
2023 (b) NULL, implying use sender_host_name and
2024 sender_host_aliases, looking them up if required, or
2025 (c) the empty string, meaning that only IP address matches
2026 are permitted
059ec3d9
PH
2027 host_address the host address
2028 host_ipv4 the IPv4 address taken from an IPv6 one
2029
2030Returns: OK matched
2031 FAIL did not match
2032 DEFER lookup deferred
32d668a5
PH
2033 ERROR (a) failed to find the host name or IP address, or
2034 (b) unknown lookup type specified, or
2035 (c) host name encountered when only IP addresses are
2036 being matched
059ec3d9
PH
2037*/
2038
32d668a5 2039int
059ec3d9
PH
2040check_host(void *arg, uschar *ss, uschar **valueptr, uschar **error)
2041{
2042check_host_block *cb = (check_host_block *)arg;
32d668a5 2043int mlen = -1;
059ec3d9 2044int maskoffset;
32d668a5 2045BOOL iplookup = FALSE;
059ec3d9 2046BOOL isquery = FALSE;
32d668a5 2047BOOL isiponly = cb->host_name != NULL && cb->host_name[0] == 0;
1688f43b 2048uschar *t;
32d668a5 2049uschar *semicolon;
059ec3d9
PH
2050uschar **aliases;
2051
2052/* Optimize for the special case when the pattern is "*". */
2053
2054if (*ss == '*' && ss[1] == 0) return OK;
2055
2056/* If the pattern is empty, it matches only in the case when there is no host -
2057this can occur in ACL checking for SMTP input using the -bs option. In this
2058situation, the host address is the empty string. */
2059
2060if (cb->host_address[0] == 0) return (*ss == 0)? OK : FAIL;
2061if (*ss == 0) return FAIL;
2062
32d668a5
PH
2063/* If the pattern is precisely "@" then match against the primary host name,
2064provided that host name matching is permitted; if it's "@[]" match against the
2065local host's IP addresses. */
059ec3d9
PH
2066
2067if (*ss == '@')
2068 {
32d668a5
PH
2069 if (ss[1] == 0)
2070 {
2071 if (isiponly) return ERROR;
2072 ss = primary_hostname;
2073 }
059ec3d9
PH
2074 else if (Ustrcmp(ss, "@[]") == 0)
2075 {
2076 ip_address_item *ip;
2077 for (ip = host_find_interfaces(); ip != NULL; ip = ip->next)
2078 if (Ustrcmp(ip->address, cb->host_address) == 0) return OK;
2079 return FAIL;
2080 }
2081 }
2082
2083/* If the pattern is an IP address, optionally followed by a bitmask count, do
2084a (possibly masked) comparision with the current IP address. */
2085
7e66e54d 2086if (string_is_ip_address(ss, &maskoffset) != 0)
059ec3d9
PH
2087 return (host_is_in_net(cb->host_address, ss, maskoffset)? OK : FAIL);
2088
1688f43b
PH
2089/* The pattern is not an IP address. A common error that people make is to omit
2090one component of an IPv4 address, either by accident, or believing that, for
2091example, 1.2.3/24 is the same as 1.2.3.0/24, or 1.2.3 is the same as 1.2.3.0,
2092which it isn't. (Those applications that do accept 1.2.3 as an IP address
2093interpret it as 1.2.0.3 because the final component becomes 16-bit - this is an
2094ancient specification.) To aid in debugging these cases, we give a specific
2095error if the pattern contains only digits and dots or contains a slash preceded
2096only by digits and dots (a slash at the start indicates a file name and of
2097course slashes may be present in lookups, but not preceded only by digits and
2098dots). */
2099
2100for (t = ss; isdigit(*t) || *t == '.'; t++);
2101if (*t == 0 || (*t == '/' && t != ss))
2102 {
2103 *error = US"malformed IPv4 address or address mask";
2104 return ERROR;
2105 }
2106
32d668a5 2107/* See if there is a semicolon in the pattern */
059ec3d9 2108
32d668a5
PH
2109semicolon = Ustrchr(ss, ';');
2110
2111/* If we are doing an IP address only match, then all lookups must be IP
df199fec 2112address lookups, even if there is no "net-". */
32d668a5
PH
2113
2114if (isiponly)
059ec3d9 2115 {
32d668a5
PH
2116 iplookup = semicolon != NULL;
2117 }
059ec3d9 2118
32d668a5 2119/* Otherwise, if the item is of the form net[n]-lookup;<file|query> then it is
df199fec
PH
2120a lookup on a masked IP network, in textual form. We obey this code even if we
2121have already set iplookup, so as to skip over the "net-" prefix and to set the
2122mask length. The net- stuff really only applies to single-key lookups where the
2123key is implicit. For query-style lookups the key is specified in the query.
2124From release 4.30, the use of net- for query style is no longer needed, but we
2125retain it for backward compatibility. */
2126
2127if (Ustrncmp(ss, "net", 3) == 0 && semicolon != NULL)
32d668a5
PH
2128 {
2129 mlen = 0;
2130 for (t = ss + 3; isdigit(*t); t++) mlen = mlen * 10 + *t - '0';
2131 if (mlen == 0 && t == ss+3) mlen = -1; /* No mask supplied */
2132 iplookup = (*t++ == '-');
2133 }
1688f43b 2134else t = ss;
059ec3d9 2135
32d668a5 2136/* Do the IP address lookup if that is indeed what we have */
059ec3d9 2137
32d668a5
PH
2138if (iplookup)
2139 {
2140 int insize;
2141 int search_type;
2142 int incoming[4];
2143 void *handle;
2144 uschar *filename, *key, *result;
2145 uschar buffer[64];
059ec3d9 2146
32d668a5 2147 /* Find the search type */
059ec3d9 2148
32d668a5 2149 search_type = search_findtype(t, semicolon - t);
059ec3d9 2150
32d668a5
PH
2151 if (search_type < 0) log_write(0, LOG_MAIN|LOG_PANIC_DIE, "%s",
2152 search_error_message);
059ec3d9 2153
13b685f9
PH
2154 /* Adjust parameters for the type of lookup. For a query-style lookup, there
2155 is no file name, and the "key" is just the query. For query-style with a file
2156 name, we have to fish the file off the start of the query. For a single-key
2157 lookup, the key is the current IP address, masked appropriately, and
2158 reconverted to text form, with the mask appended. For IPv6 addresses, specify
2159 dot separators instead of colons. */
059ec3d9 2160
13b685f9
PH
2161 if (mac_islookup(search_type, lookup_absfilequery))
2162 {
2163 filename = semicolon + 1;
2164 key = filename;
2165 while (*key != 0 && !isspace(*key)) key++;
2166 filename = string_copyn(filename, key - filename);
2167 while (isspace(*key)) key++;
2168 }
2169 else if (mac_islookup(search_type, lookup_querystyle))
32d668a5
PH
2170 {
2171 filename = NULL;
2172 key = semicolon + 1;
2173 }
2174 else
2175 {
2176 insize = host_aton(cb->host_address, incoming);
2177 host_mask(insize, incoming, mlen);
2178 (void)host_nmtoa(insize, incoming, mlen, buffer, '.');
2179 key = buffer;
2180 filename = semicolon + 1;
059ec3d9 2181 }
32d668a5
PH
2182
2183 /* Now do the actual lookup; note that there is no search_close() because
2184 of the caching arrangements. */
2185
2186 handle = search_open(filename, search_type, 0, NULL, NULL);
2187 if (handle == NULL) log_write(0, LOG_MAIN|LOG_PANIC_DIE, "%s",
2188 search_error_message);
2189 result = search_find(handle, filename, key, -1, NULL, 0, 0, NULL);
2190 if (valueptr != NULL) *valueptr = result;
2191 return (result != NULL)? OK : search_find_defer? DEFER: FAIL;
059ec3d9
PH
2192 }
2193
2194/* The pattern is not an IP address or network reference of any kind. That is,
32d668a5
PH
2195it is a host name pattern. If this is an IP only match, there's an error in the
2196host list. */
2197
2198if (isiponly)
2199 {
2200 *error = US"cannot match host name in match_ip list";
2201 return ERROR;
2202 }
2203
2204/* Check the characters of the pattern to see if they comprise only letters,
2205digits, full stops, and hyphens (the constituents of domain names). Allow
2206underscores, as they are all too commonly found. Sigh. Also, if
2207allow_utf8_domains is set, allow top-bit characters. */
059ec3d9
PH
2208
2209for (t = ss; *t != 0; t++)
2210 if (!isalnum(*t) && *t != '.' && *t != '-' && *t != '_' &&
2211 (!allow_utf8_domains || *t < 128)) break;
2212
2213/* If the pattern is a complete domain name, with no fancy characters, look up
2214its IP address and match against that. Note that a multi-homed host will add
2215items to the chain. */
2216
2217if (*t == 0)
2218 {
2219 int rc;
2220 host_item h;
2221 h.next = NULL;
2222 h.name = ss;
2223 h.address = NULL;
2224 h.mx = MX_NONE;
9b8fadde 2225
059ec3d9
PH
2226 rc = host_find_byname(&h, NULL, NULL, FALSE);
2227 if (rc == HOST_FOUND || rc == HOST_FOUND_LOCAL)
2228 {
2229 host_item *hh;
2230 for (hh = &h; hh != NULL; hh = hh->next)
2231 {
96776534 2232 if (host_is_in_net(hh->address, cb->host_address, 0)) return OK;
059ec3d9
PH
2233 }
2234 return FAIL;
2235 }
2236 if (rc == HOST_FIND_AGAIN) return DEFER;
2237 *error = string_sprintf("failed to find IP address for %s", ss);
2238 return ERROR;
2239 }
2240
2241/* Almost all subsequent comparisons require the host name, and can be done
2242using the general string matching function. When this function is called for
2243outgoing hosts, the name is always given explicitly. If it is NULL, it means we
2244must use sender_host_name and its aliases, looking them up if necessary. */
2245
2246if (cb->host_name != NULL) /* Explicit host name given */
2247 return match_check_string(cb->host_name, ss, -1, TRUE, TRUE, TRUE,
2248 valueptr);
2249
2250/* Host name not given; in principle we need the sender host name and its
2251aliases. However, for query-style lookups, we do not need the name if the
2252query does not contain $sender_host_name. From release 4.23, a reference to
2253$sender_host_name causes it to be looked up, so we don't need to do the lookup
2254on spec. */
2255
2256if ((semicolon = Ustrchr(ss, ';')) != NULL)
2257 {
2258 uschar *affix;
2259 int partial, affixlen, starflags, id;
2260
2261 *semicolon = 0;
2262 id = search_findtype_partial(ss, &partial, &affix, &affixlen, &starflags);
2263 *semicolon=';';
2264
2265 if (id < 0) /* Unknown lookup type */
2266 {
2267 log_write(0, LOG_MAIN|LOG_PANIC, "%s in host list item \"%s\"",
2268 search_error_message, ss);
2269 return DEFER;
2270 }
13b685f9 2271 isquery = mac_islookup(id, lookup_querystyle|lookup_absfilequery);
059ec3d9
PH
2272 }
2273
2274if (isquery)
2275 {
2276 switch(match_check_string(US"", ss, -1, TRUE, TRUE, TRUE, valueptr))
2277 {
2278 case OK: return OK;
2279 case DEFER: return DEFER;
2280 default: return FAIL;
2281 }
2282 }
2283
2284/* Not a query-style lookup; must ensure the host name is present, and then we
2285do a check on the name and all its aliases. */
2286
2287if (sender_host_name == NULL)
2288 {
2289 HDEBUG(D_host_lookup)
2290 debug_printf("sender host name required, to match against %s\n", ss);
2291 if (host_lookup_failed || host_name_lookup() != OK)
2292 {
2293 *error = string_sprintf("failed to find host name for %s",
2294 sender_host_address);;
2295 return ERROR;
2296 }
2297 host_build_sender_fullhost();
2298 }
2299
2300/* Match on the sender host name, using the general matching function */
2301
2302switch(match_check_string(sender_host_name, ss, -1, TRUE, TRUE, TRUE,
2303 valueptr))
2304 {
2305 case OK: return OK;
2306 case DEFER: return DEFER;
2307 }
2308
2309/* If there are aliases, try matching on them. */
2310
2311aliases = sender_host_aliases;
2312while (*aliases != NULL)
2313 {
2314 switch(match_check_string(*aliases++, ss, -1, TRUE, TRUE, TRUE, valueptr))
2315 {
2316 case OK: return OK;
2317 case DEFER: return DEFER;
2318 }
2319 }
2320return FAIL;
2321}
2322
2323
2324
2325
2326/*************************************************
2327* Check a specific host matches a host list *
2328*************************************************/
2329
2330/* This function is passed a host list containing items in a number of
2331different formats and the identity of a host. Its job is to determine whether
2332the given host is in the set of hosts defined by the list. The host name is
2333passed as a pointer so that it can be looked up if needed and not already
2334known. This is commonly the case when called from verify_check_host() to check
2335an incoming connection. When called from elsewhere the host name should usually
2336be set.
2337
2338This function is now just a front end to match_check_list(), which runs common
2339code for scanning a list. We pass it the check_host() function to perform a
2340single test.
2341
2342Arguments:
2343 listptr pointer to the host list
2344 cache_bits pointer to cache for named lists, or NULL
2345 host_name the host name or NULL, implying use sender_host_name and
2346 sender_host_aliases, looking them up if required
2347 host_address the IP address
2348 valueptr if not NULL, data from a lookup is passed back here
2349
2350Returns: OK if the host is in the defined set
2351 FAIL if the host is not in the defined set,
2352 DEFER if a data lookup deferred (not a host lookup)
2353
2354If the host name was needed in order to make a comparison, and could not be
2355determined from the IP address, the result is FAIL unless the item
2356"+allow_unknown" was met earlier in the list, in which case OK is returned. */
2357
2358int
2359verify_check_this_host(uschar **listptr, unsigned int *cache_bits,
2360 uschar *host_name, uschar *host_address, uschar **valueptr)
2361{
d4eb88df 2362int rc;
059ec3d9 2363unsigned int *local_cache_bits = cache_bits;
d4eb88df 2364uschar *save_host_address = deliver_host_address;
059ec3d9
PH
2365check_host_block cb;
2366cb.host_name = host_name;
2367cb.host_address = host_address;
2368
2369if (valueptr != NULL) *valueptr = NULL;
2370
2371/* If the host address starts off ::ffff: it is an IPv6 address in
2372IPv4-compatible mode. Find the IPv4 part for checking against IPv4
2373addresses. */
2374
2375cb.host_ipv4 = (Ustrncmp(host_address, "::ffff:", 7) == 0)?
2376 host_address + 7 : host_address;
2377
8e669ac1
PH
2378/* During the running of the check, put the IP address into $host_address. In
2379the case of calls from the smtp transport, it will already be there. However,
2380in other calls (e.g. when testing ignore_target_hosts), it won't. Just to be on
d4eb88df
PH
2381the safe side, any existing setting is preserved, though as I write this
2382(November 2004) I can't see any cases where it is actually needed. */
2383
2384deliver_host_address = host_address;
2385rc = match_check_list(
2386 listptr, /* the list */
2387 0, /* separator character */
2388 &hostlist_anchor, /* anchor pointer */
2389 &local_cache_bits, /* cache pointer */
2390 check_host, /* function for testing */
2391 &cb, /* argument for function */
2392 MCL_HOST, /* type of check */
8e669ac1 2393 (host_address == sender_host_address)?
d4eb88df
PH
2394 US"host" : host_address, /* text for debugging */
2395 valueptr); /* where to pass back data */
2396deliver_host_address = save_host_address;
8e669ac1 2397return rc;
059ec3d9
PH
2398}
2399
2400
2401
2402
2403/*************************************************
2404* Check the remote host matches a list *
2405*************************************************/
2406
2407/* This is a front end to verify_check_this_host(), created because checking
2408the remote host is a common occurrence. With luck, a good compiler will spot
2409the tail recursion and optimize it. If there's no host address, this is
2410command-line SMTP input - check against an empty string for the address.
2411
2412Arguments:
2413 listptr pointer to the host list
2414
2415Returns: the yield of verify_check_this_host(),
2416 i.e. OK, FAIL, or DEFER
2417*/
2418
2419int
2420verify_check_host(uschar **listptr)
2421{
2422return verify_check_this_host(listptr, sender_host_cache, NULL,
2423 (sender_host_address == NULL)? US"" : sender_host_address, NULL);
2424}
2425
2426
2427
2428
2429
2430/*************************************************
2431* Invert an IP address for a DNS black list *
2432*************************************************/
2433
2434/*
2435Arguments:
2436 buffer where to put the answer
2437 address the address to invert
2438*/
2439
2440static void
2441invert_address(uschar *buffer, uschar *address)
2442{
2443int bin[4];
2444uschar *bptr = buffer;
2445
2446/* If this is an IPv4 address mapped into IPv6 format, adjust the pointer
2447to the IPv4 part only. */
2448
2449if (Ustrncmp(address, "::ffff:", 7) == 0) address += 7;
2450
2451/* Handle IPv4 address: when HAVE_IPV6 is false, the result of host_aton() is
2452always 1. */
2453
2454if (host_aton(address, bin) == 1)
2455 {
2456 int i;
2457 int x = bin[0];
2458 for (i = 0; i < 4; i++)
2459 {
2460 sprintf(CS bptr, "%d.", x & 255);
2461 while (*bptr) bptr++;
2462 x >>= 8;
2463 }
2464 }
2465
2466/* Handle IPv6 address. Actually, as far as I know, there are no IPv6 addresses
2467in any DNS black lists, and the format in which they will be looked up is
2468unknown. This is just a guess. */
2469
2470#if HAVE_IPV6
2471else
2472 {
2473 int i, j;
2474 for (j = 3; j >= 0; j--)
2475 {
2476 int x = bin[j];
2477 for (i = 0; i < 8; i++)
2478 {
2479 sprintf(CS bptr, "%x.", x & 15);
2480 while (*bptr) bptr++;
2481 x >>= 4;
2482 }
2483 }
2484 }
2485#endif
2486}
2487
2488
2489
2490/*************************************************
0bcb2a0e
PH
2491* Perform a single dnsbl lookup *
2492*************************************************/
2493
2494/* This function is called from verify_check_dnsbl() below.
2495
2496Arguments:
2497 domain the outer dnsbl domain (for debug message)
8e669ac1 2498 keydomain the current keydomain (for debug message)
0bcb2a0e 2499 query the domain to be looked up
8e669ac1
PH
2500 iplist the list of matching IP addresses
2501 bitmask true if bitmask matching is wanted
2502 invert_result true if result to be inverted
2503 defer_return what to return for a defer
0bcb2a0e
PH
2504
2505Returns: OK if lookup succeeded
2506 FAIL if not
2507*/
2508
2509static int
8e669ac1 2510one_check_dnsbl(uschar *domain, uschar *keydomain, uschar *query,
0bcb2a0e 2511 uschar *iplist, BOOL bitmask, BOOL invert_result, int defer_return)
8e669ac1 2512{
0bcb2a0e
PH
2513dns_answer dnsa;
2514dns_scan dnss;
2515tree_node *t;
2516dnsbl_cache_block *cb;
2517int old_pool = store_pool;
2518
2519/* Look for this query in the cache. */
2520
2521t = tree_search(dnsbl_cache, query);
2522
2523/* If not cached from a previous lookup, we must do a DNS lookup, and
2524cache the result in permanent memory. */
2525
2526if (t == NULL)
2527 {
2528 store_pool = POOL_PERM;
2529
2530 /* Set up a tree entry to cache the lookup */
2531
2532 t = store_get(sizeof(tree_node) + Ustrlen(query));
2533 Ustrcpy(t->name, query);
2534 t->data.ptr = cb = store_get(sizeof(dnsbl_cache_block));
2535 (void)tree_insertnode(&dnsbl_cache, t);
2536
2537 /* Do the DNS loopup . */
2538
2539 HDEBUG(D_dnsbl) debug_printf("new DNS lookup for %s\n", query);
2540 cb->rc = dns_basic_lookup(&dnsa, query, T_A);
2541 cb->text_set = FALSE;
2542 cb->text = NULL;
2543 cb->rhs = NULL;
2544
2545 /* If the lookup succeeded, cache the RHS address. The code allows for
2546 more than one address - this was for complete generality and the possible
2547 use of A6 records. However, A6 records have been reduced to experimental
2548 status (August 2001) and may die out. So they may never get used at all,
2549 let alone in dnsbl records. However, leave the code here, just in case.
2550
2551 Quite apart from one A6 RR generating multiple addresses, there are DNS
2552 lists that return more than one A record, so we must handle multiple
2553 addresses generated in that way as well. */
2554
2555 if (cb->rc == DNS_SUCCEED)
2556 {
2557 dns_record *rr;
2558 dns_address **addrp = &(cb->rhs);
2559 for (rr = dns_next_rr(&dnsa, &dnss, RESET_ANSWERS);
2560 rr != NULL;
2561 rr = dns_next_rr(&dnsa, &dnss, RESET_NEXT))
2562 {
2563 if (rr->type == T_A)
2564 {
2565 dns_address *da = dns_address_from_rr(&dnsa, rr);
2566 if (da != NULL)
2567 {
2568 *addrp = da;
2569 while (da->next != NULL) da = da->next;
2570 addrp = &(da->next);
2571 }
2572 }
2573 }
2574
2575 /* If we didn't find any A records, change the return code. This can
2576 happen when there is a CNAME record but there are no A records for what
2577 it points to. */
2578
2579 if (cb->rhs == NULL) cb->rc = DNS_NODATA;
2580 }
2581
2582 store_pool = old_pool;
2583 }
2584
2585/* Previous lookup was cached */
2586
2587else
2588 {
2589 HDEBUG(D_dnsbl) debug_printf("using result of previous DNS lookup\n");
2590 cb = t->data.ptr;
2591 }
2592
2593/* We now have the result of the DNS lookup, either newly done, or cached
2594from a previous call. If the lookup succeeded, check against the address
2595list if there is one. This may be a positive equality list (introduced by
2596"="), a negative equality list (introduced by "!="), a positive bitmask
2597list (introduced by "&"), or a negative bitmask list (introduced by "!&").*/
2598
2599if (cb->rc == DNS_SUCCEED)
2600 {
2601 dns_address *da = NULL;
2602 uschar *addlist = cb->rhs->address;
2603
2604 /* For A and AAAA records, there may be multiple addresses from multiple
2605 records. For A6 records (currently not expected to be used) there may be
2606 multiple addresses from a single record. */
2607
2608 for (da = cb->rhs->next; da != NULL; da = da->next)
2609 addlist = string_sprintf("%s, %s", addlist, da->address);
2610
2611 HDEBUG(D_dnsbl) debug_printf("DNS lookup for %s succeeded (yielding %s)\n",
2612 query, addlist);
2613
2614 /* Address list check; this can be either for equality, or via a bitmask.
2615 In the latter case, all the bits must match. */
2616
2617 if (iplist != NULL)
2618 {
2619 int ipsep = ',';
2620 uschar ip[46];
2621 uschar *ptr = iplist;
2622
2623 while (string_nextinlist(&ptr, &ipsep, ip, sizeof(ip)) != NULL)
2624 {
2625 /* Handle exact matching */
2626 if (!bitmask)
2627 {
2628 for (da = cb->rhs; da != NULL; da = da->next)
2629 {
2630 if (Ustrcmp(CS da->address, ip) == 0) break;
2631 }
2632 }
2633 /* Handle bitmask matching */
2634 else
2635 {
2636 int address[4];
2637 int mask = 0;
2638
2639 /* At present, all known DNS blocking lists use A records, with
2640 IPv4 addresses on the RHS encoding the information they return. I
2641 wonder if this will linger on as the last vestige of IPv4 when IPv6
2642 is ubiquitous? Anyway, for now we use paranoia code to completely
2643 ignore IPv6 addresses. The default mask is 0, which always matches.
2644 We change this only for IPv4 addresses in the list. */
2645
2646 if (host_aton(ip, address) == 1) mask = address[0];
2647
2648 /* Scan the returned addresses, skipping any that are IPv6 */
2649
2650 for (da = cb->rhs; da != NULL; da = da->next)
2651 {
2652 if (host_aton(da->address, address) != 1) continue;
2653 if ((address[0] & mask) == mask) break;
2654 }
2655 }
2656
2657 /* Break out if a match has been found */
2658
2659 if (da != NULL) break;
2660 }
2661
2662 /* If either
2663
2664 (a) No IP address in a positive list matched, or
2665 (b) An IP address in a negative list did match
2666
2667 then behave as if the DNSBL lookup had not succeeded, i.e. the host is
2668 not on the list. */
2669
2670 if (invert_result != (da == NULL))
2671 {
2672 HDEBUG(D_dnsbl)
2673 {
2674 debug_printf("=> but we are not accepting this block class because\n");
2675 debug_printf("=> there was %s match for %c%s\n",
2676 invert_result? "an exclude":"no", bitmask? '&' : '=', iplist);
2677 }
8e669ac1 2678 return FAIL;
0bcb2a0e
PH
2679 }
2680 }
2681
2682 /* Either there was no IP list, or the record matched. Look up a TXT record
2683 if it hasn't previously been done. */
2684
2685 if (!cb->text_set)
2686 {
2687 cb->text_set = TRUE;
2688 if (dns_basic_lookup(&dnsa, query, T_TXT) == DNS_SUCCEED)
2689 {
2690 dns_record *rr;
2691 for (rr = dns_next_rr(&dnsa, &dnss, RESET_ANSWERS);
2692 rr != NULL;
2693 rr = dns_next_rr(&dnsa, &dnss, RESET_NEXT))
2694 if (rr->type == T_TXT) break;
2695 if (rr != NULL)
2696 {
2697 int len = (rr->data)[0];
2698 if (len > 511) len = 127;
2699 store_pool = POOL_PERM;
2700 cb->text = string_sprintf("%.*s", len, (const uschar *)(rr->data+1));
2701 store_pool = old_pool;
2702 }
2703 }
2704 }
2705
2706 dnslist_value = addlist;
2707 dnslist_text = cb->text;
2708 return OK;
2709 }
2710
2711/* There was a problem with the DNS lookup */
2712
2713if (cb->rc != DNS_NOMATCH && cb->rc != DNS_NODATA)
2714 {
2715 log_write(L_dnslist_defer, LOG_MAIN,
2716 "DNS list lookup defer (probably timeout) for %s: %s", query,
2717 (defer_return == OK)? US"assumed in list" :
2718 (defer_return == FAIL)? US"assumed not in list" :
2719 US"returned DEFER");
2720 return defer_return;
2721 }
2722
2723/* No entry was found in the DNS; continue for next domain */
2724
2725HDEBUG(D_dnsbl)
2726 {
2727 debug_printf("DNS lookup for %s failed\n", query);
2728 debug_printf("=> that means %s is not listed at %s\n",
2729 keydomain, domain);
2730 }
2731
2732return FAIL;
2733}
2734
2735
2736
2737
2738/*************************************************
059ec3d9
PH
2739* Check host against DNS black lists *
2740*************************************************/
2741
2742/* This function runs checks against a list of DNS black lists, until one
2743matches. Each item on the list can be of the form
2744
2745 domain=ip-address/key
2746
2747The domain is the right-most domain that is used for the query, for example,
2748blackholes.mail-abuse.org. If the IP address is present, there is a match only
2749if the DNS lookup returns a matching IP address. Several addresses may be
2750given, comma-separated, for example: x.y.z=127.0.0.1,127.0.0.2.
2751
2752If no key is given, what is looked up in the domain is the inverted IP address
2753of the current client host. If a key is given, it is used to construct the
2754domain for the lookup. For example,
2755
2756 dsn.rfc-ignorant.org/$sender_address_domain
2757
2758After finding a match in the DNS, the domain is placed in $dnslist_domain, and
2759then we check for a TXT record for an error message, and if found, save its
2760value in $dnslist_text. We also cache everything in a tree, to optimize
2761multiple lookups.
2762
2763Note: an address for testing RBL is 192.203.178.39
2764Note: an address for testing DUL is 192.203.178.4
2765Note: a domain for testing RFCI is example.tld.dsn.rfc-ignorant.org
2766
2767Arguments:
2768 listptr the domain/address/data list
2769
2770Returns: OK successful lookup (i.e. the address is on the list), or
2771 lookup deferred after +include_unknown
2772 FAIL name not found, or no data found for the given type, or
2773 lookup deferred after +exclude_unknown (default)
2774 DEFER lookup failure, if +defer_unknown was set
2775*/
2776
2777int
2778verify_check_dnsbl(uschar **listptr)
2779{
2780int sep = 0;
2781int defer_return = FAIL;
059ec3d9
PH
2782BOOL invert_result = FALSE;
2783uschar *list = *listptr;
2784uschar *domain;
2785uschar *s;
2786uschar buffer[1024];
2787uschar query[256]; /* DNS domain max length */
2788uschar revadd[128]; /* Long enough for IPv6 address */
2789
2790/* Indicate that the inverted IP address is not yet set up */
2791
2792revadd[0] = 0;
2793
0bcb2a0e
PH
2794/* In case this is the first time the DNS resolver is being used. */
2795
2796dns_init(FALSE, FALSE);
2797
059ec3d9
PH
2798/* Loop through all the domains supplied, until something matches */
2799
2800while ((domain = string_nextinlist(&list, &sep, buffer, sizeof(buffer))) != NULL)
2801 {
0bcb2a0e 2802 int rc;
059ec3d9
PH
2803 BOOL frc;
2804 BOOL bitmask = FALSE;
059ec3d9
PH
2805 uschar *iplist;
2806 uschar *key;
059ec3d9
PH
2807
2808 HDEBUG(D_dnsbl) debug_printf("DNS list check: %s\n", domain);
2809
2810 /* Deal with special values that change the behaviour on defer */
2811
2812 if (domain[0] == '+')
2813 {
2814 if (strcmpic(domain, US"+include_unknown") == 0) defer_return = OK;
2815 else if (strcmpic(domain, US"+exclude_unknown") == 0) defer_return = FAIL;
2816 else if (strcmpic(domain, US"+defer_unknown") == 0) defer_return = DEFER;
2817 else
2818 log_write(0, LOG_MAIN|LOG_PANIC, "unknown item in dnslist (ignored): %s",
2819 domain);
2820 continue;
2821 }
2822
2823 /* See if there's explicit data to be looked up */
2824
2825 key = Ustrchr(domain, '/');
2826 if (key != NULL) *key++ = 0;
2827
2828 /* See if there's a list of addresses supplied after the domain name. This is
2829 introduced by an = or a & character; if preceded by ! we invert the result.
2830 */
2831
2832 iplist = Ustrchr(domain, '=');
2833 if (iplist == NULL)
2834 {
2835 bitmask = TRUE;
2836 iplist = Ustrchr(domain, '&');
2837 }
2838
2839 if (iplist != NULL)
2840 {
2841 if (iplist > domain && iplist[-1] == '!')
2842 {
2843 invert_result = TRUE;
2844 iplist[-1] = 0;
2845 }
2846 *iplist++ = 0;
2847 }
2848
2849 /* Check that what we have left is a sensible domain name. There is no reason
2850 why these domains should in fact use the same syntax as hosts and email
2851 domains, but in practice they seem to. However, there is little point in
2852 actually causing an error here, because that would no doubt hold up incoming
2853 mail. Instead, I'll just log it. */
2854
2855 for (s = domain; *s != 0; s++)
2856 {
2857 if (!isalnum(*s) && *s != '-' && *s != '.')
2858 {
2859 log_write(0, LOG_MAIN, "dnslists domain \"%s\" contains "
2860 "strange characters - is this right?", domain);
2861 break;
2862 }
2863 }
2864
8e669ac1 2865 /* If there is no key string, construct the query by adding the domain name
0bcb2a0e 2866 onto the inverted host address, and perform a single DNS lookup. */
8e669ac1 2867
059ec3d9
PH
2868 if (key == NULL)
2869 {
2870 if (sender_host_address == NULL) return FAIL; /* can never match */
2871 if (revadd[0] == 0) invert_address(revadd, sender_host_address);
2872 frc = string_format(query, sizeof(query), "%s%s", revadd, domain);
8e669ac1 2873
0bcb2a0e 2874 if (!frc)
059ec3d9 2875 {
0bcb2a0e
PH
2876 log_write(0, LOG_MAIN|LOG_PANIC, "dnslist query is too long "
2877 "(ignored): %s...", query);
2878 continue;
059ec3d9 2879 }
8e669ac1
PH
2880
2881 rc = one_check_dnsbl(domain, sender_host_address, query, iplist, bitmask,
0bcb2a0e 2882 invert_result, defer_return);
8e669ac1 2883
0bcb2a0e
PH
2884 if (rc == OK)
2885 {
2886 dnslist_domain = string_copy(domain);
8e669ac1 2887 HDEBUG(D_dnsbl) debug_printf("=> that means %s is listed at %s\n",
0bcb2a0e
PH
2888 sender_host_address, domain);
2889 }
8e669ac1 2890
0bcb2a0e 2891 if (rc != FAIL) return rc; /* OK or DEFER */
059ec3d9 2892 }
8e669ac1
PH
2893
2894 /* If there is a key string, it can be a list of domains or IP addresses to
0bcb2a0e 2895 be concatenated with the main domain. */
8e669ac1 2896
059ec3d9
PH
2897 else
2898 {
0bcb2a0e 2899 int keysep = 0;
8e669ac1
PH
2900 BOOL defer = FALSE;
2901 uschar *keydomain;
0bcb2a0e 2902 uschar keybuffer[256];
8e669ac1
PH
2903
2904 while ((keydomain = string_nextinlist(&key, &keysep, keybuffer,
0bcb2a0e 2905 sizeof(keybuffer))) != NULL)
8e669ac1 2906 {
7e66e54d 2907 if (string_is_ip_address(keydomain, NULL) != 0)
059ec3d9 2908 {
0bcb2a0e
PH
2909 uschar keyrevadd[128];
2910 invert_address(keyrevadd, keydomain);
8e669ac1 2911 frc = string_format(query, sizeof(query), "%s%s", keyrevadd, domain);
0bcb2a0e
PH
2912 }
2913 else
8e669ac1 2914 {
0bcb2a0e 2915 frc = string_format(query, sizeof(query), "%s.%s", keydomain, domain);
059ec3d9
PH
2916 }
2917
0bcb2a0e 2918 if (!frc)
059ec3d9 2919 {
0bcb2a0e
PH
2920 log_write(0, LOG_MAIN|LOG_PANIC, "dnslist query is too long "
2921 "(ignored): %s...", query);
2922 continue;
059ec3d9 2923 }
8e669ac1
PH
2924
2925 rc = one_check_dnsbl(domain, keydomain, query, iplist, bitmask,
0bcb2a0e 2926 invert_result, defer_return);
8e669ac1 2927
0bcb2a0e 2928 if (rc == OK)
059ec3d9 2929 {
0bcb2a0e 2930 dnslist_domain = string_copy(domain);
8e669ac1 2931 HDEBUG(D_dnsbl) debug_printf("=> that means %s is listed at %s\n",
0bcb2a0e 2932 keydomain, domain);
8e669ac1 2933 return OK;
059ec3d9 2934 }
8e669ac1 2935
c38d6da9
PH
2936 /* If the lookup deferred, remember this fact. We keep trying the rest
2937 of the list to see if we get a useful result, and if we don't, we return
2938 DEFER at the end. */
059ec3d9 2939
c38d6da9 2940 if (rc == DEFER) defer = TRUE;
0bcb2a0e 2941 } /* continue with next keystring domain/address */
c38d6da9
PH
2942
2943 if (defer) return DEFER;
8e669ac1 2944 }
0bcb2a0e 2945 } /* continue with next dnsdb outer domain */
059ec3d9
PH
2946
2947return FAIL;
2948}
2949
2950/* End of verify.c */